Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each...

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun. In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than at the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas. This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

In paragraph 1, why does the author compare the structure of an atom to a solar system?

A. To provide an explanation of atomic structure that will be easily understood

B. To show the influence of atomic structure on the world at the observable level

C. To show that the complex mathematical formulas used to explain atomic structure are inaccurate

D. To contrast the size of atoms with the size of objects at the observable level

1

DH

Dương Hoàn Anh

21 tháng 4 2018

Chọn A

Kiến thức: Đọc hiểu

Giải thích:

Trong đoạn 1, tại sao tác giả lại so sánh cấu trúc của một nguyên tử với hệ Mặt Trời?

A. Để đưa ra một lời giải thích về cấu trúc nguyên tử một cách dễ hiểu.

B. Để chỉ ra ảnh hưởng của cấu trúc nguyên tử đến thế giới ở cấp độ quan sát được.

C. Để chỉ ra rằng các công thức toán học phức tạp được sử dụng để giải thích cấu trúc nguyên tử là không chính xác.

D. Để tương phản kích thước của các nguyên tử với kích thước của các vật thể ở mức có thể quan sát được.

Thông tin: The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun.

Tạm dịch: Cấu trúc của một nguyên tử có thể được mô tả chính xác nhất giống như một hệ mặt trời nhỏ, với các nơtron ở trung tâm và các electron quay quanh chúng theo các quỹ đạo khác nhau, giống như các hành tinh quay quanh Mặt Trời

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions. Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in...

LQ

Lê Quỳnh Anh

12 tháng 1 2017

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun. In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than at the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas. This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached

The word "stable" in bold in paragraph 2 is closest in meaning to _____.

A. neutral

B. unchanging

C. equal

D. heavy

1

DH

Dương Hoàn Anh

12 tháng 1 2017

Chọn B

Kiến thức: Đọc hiểu

Giải thích:

Từ "stable" được in đậm trong đoạn 2 có nghĩa gần nhất với _____.

A. trung tính

B. không thay đổi

C. bằng

D. nặng

Thông tin: In most lighter atoms, the number of neutrons and protons is equal, and the element is stable.

Tạm dịch: Trong hầu hết các nguyên tử nhẹ hơn, số lượng nơtron và proton bằng nhau và nguyên tố này bền vững

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questionsAtomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in...

LQ

Lê Quỳnh Anh

2 tháng 12 2018

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun. In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than at the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas. This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps to keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbits. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electrons than the previous shell. Electrons naturally seek to occupy the lowest shell possible. So, if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light. This is why fires and other very hot objects seem to glow

According to the information in paragraph 2, what will happen if an atom has more neutrons than protons?

A. It will not have enough of a positive electrical charge to keep its electrons in orbit

B. Its extra neutrons will be converted into light energy

C. It will slowly give off neutrons until the atom becomes stable

D. Its nucleus will explode in a supernova

1

DH

Dương Hoàn Anh

2 tháng 12 2018

Chọn C

Kiến thức: Đọc hiểu

Giải thích: 20

Theo thông tin trong đoạn 2, điều gì sẽ xảy ra nếu một nguyên tử có nhiều nơtron hơn proton?

A. Nó sẽ không có đủ điện tích dương để giữ các electron của nó trong quỹ đạo.

B. Các nơtron thừa ra của nó sẽ được chuyển thành năng lượng ánh sáng.

C. Nó sẽ từ từ giải phóng nơtron cho đến khi nguyên tử trở về dạng bền vững.

D. Hạt nhân của nó sẽ phát nổ trong một sao băng.

Thông tin: In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Tạm dịch: Tuy nhiên, trong các nguyên tử nặng hơn, có nhiều nơtron hơn proton và nguyên tố này không bền vững, cuối cùng mất đi nơtron thông qua sự phân rã phóng xạ cho đến khi đạt được trạng thái cân bằng

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in...

LQ

Lê Quỳnh Anh

10 tháng 4 2019

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun. In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than at the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas. This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps to keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbits. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electrons than the previous shell. Electrons naturally seek to occupy the lowest shell possible. So, if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light. This is why fires and other very hot objects seem to glow.

According to paragraph 3, when does an atom produce light?

A. When it has more electrons than its electron shells can hold

B. When energy is added to the outermost electron shell

C. When an electron drops back to its original electron shell

D. When an electron is transferred from one atom to another

1

DH

Dương Hoàn Anh

10 tháng 4 2019

Chọn C

Kiến thức: Đọc hiểu

Giải thích:

Theo đoạn 3, khi nào một nguyên tử phát ra ánh sáng?

A. Khi nó có nhiều electron hơn so với số lượng mà lớp electron của nó có thể giữ được.

B. Khi năng lượng được thu thêm vào lớp electron ngoài cùng.

C. Khi một electron rơi trở lại lớp electron ban đầu của nó.

D. Khi một electron được chuyển từ nguyên tử này sang nguyên tử khác.

Thông tin: When the electrons drop back down to their natural shell, they emit light.

Tạm dịch: Khi các electron rơi trở lại lớp ban đầu của mình, chúng phát ra ánh sáng

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions. Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in...

LQ

Lê Quỳnh Anh

26 tháng 9 2018

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun. In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than at the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas. This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps to keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbits. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electrons than the previous shell. Electrons naturally seek to occupy the lowest shell possible. So, if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light. This is why fires and other very hot objects seem to glow.

The phrase "one another" in bold in paragraph 3 refers to _______.

A. electrons

B. electrical charges

C. particles

D. atoms

1

DH

Dương Hoàn Anh

26 tháng 9 2018

Chọn B

Kiến thức: Đọc hiểu

Giải thích:

Cụm từ "one another" in đậm trong đoạn 3 đề cập đến _______.

A. electron

B. các điện tích

C. các hạt

D. các nguyên tử

Thông tin: Opposite electrical charges attract one another, so the positive charge of the proton helps to keep the negatively charged electron in orbit around the nucleus of the atom.

Tạm dịch: Các điện tích trái dấu nhau thì hút nhau, vì vậy điện tích dương của proton giữ electron tích điện âm trong quỹ đạo quay xung quanh hạt nhân của nguyên tử

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade...

LQ

Lê Quỳnh Anh

27 tháng 9 2019

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun .In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than of the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas .This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers; their atomic number , which is equal to the number of protons they have, and their atomic weight , which is equal to total number of their neutrons and protons. In most lighter atoms , the number of neutrons and protons is equal , and the element is stable. In heavier atoms, however, there are more neutrons than protons , and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbit. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electron than the previous shell. Electrons naturally seek to occupy the lowest shell possible .So if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light .This is why fires and other very hot objects seem to glow.

Electrons are also primarily responsible for many of the chemical properties of atoms. Since electrons seek to occupy the lowest electron shell possible, they will move from one atom to another if there is a space available in a lower electron shell. For example, if there is an atom with an open space in its third shell, and it comes into contact with an atom with electrons in its fourth shell, the first atom will take one of these electrons to complete its third shell. When this happens, the two atoms will be chemically bonded to form a molecule. Furthermore, atoms sometimes lose electrons in collisions with other atoms. When it happens, the radio of protons and electrons in the atom changes, and therefore, the overall electrical charge of the atom changes as well. These atoms are called isotopes, and they have significantly different chemical properties from their parent atoms.

In paragraph 1, why does the author compare the structure of an atom to a solar system?

A. To provide an explanation of atomic structure that will be easily understood

B. To show that the complex mathematical formulas used to explain atomic structure are inaccurate

C. To show the influence of atomic structure on the world at the observable level

D. To contrast the size of atoms with the size of objects at the observable level

1

DH

Dương Hoàn Anh

27 tháng 9 2019

Đáp án là A

Ở đoạn 1, tại sao tác giả so sánh cấu trúc của một nguyên tử với hệ mặt trời?

A. Để cung cấp lời giải thích của cấu trúc nguyên tử sẽ được hiểu một cách dễ dàng.

B. Để cho thấy rằng những công thức toán học phức tạp được sử dụng để giải thích cấu trúc nguyên tử là không đúng.

C. Để cho thấy sự ảnh hưởng của cấu trúc phân tử lên thế giới ở mức độ có thể quan sát được.

D. Để tương phản kích thước của nguyên tử với các vật thể ở mức độ có thể quan sát đượC

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade...

LQ

Lê Quỳnh Anh

22 tháng 9 2018

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun .In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than of the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas .This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers; their atomic number , which is equal to the number of protons they have, and their atomic weight , which is equal to total number of their neutrons and protons. In most lighter atoms , the number of neutrons and protons is equal , and the element is stable. In heavier atoms, however, there are more neutrons than protons , and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbit. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electron than the previous shell. Electrons naturally seek to occupy the lowest shell possible .So if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light .This is why fires and other very hot objects seem to glow.

Electrons are also primarily responsible for many of the chemical properties of atoms. Since electrons seek to occupy the lowest electron shell possible, they will move from one atom to another if there is a space available in a lower electron shell. For example, if there is an atom with an open space in its third shell, and it comes into contact with an atom with electrons in its fourth shell, the first atom will take one of these electrons to complete its third shell. When this happens, the two atoms will be chemically bonded to form a molecule. Furthermore, atoms sometimes lose electrons in collisions with other atoms. When it happens, the radio of protons and electrons in the atom changes, and therefore, the overall electrical charge of the atom changes as well. These atoms are called isotopes, and they have significantly different chemical properties from their parent atoms.

According to the passage, all of the following are true of electrons EXCEPT

A. Their energy levels are fixed and unchanging

B. They are kept in orbit by electromagnetic attraction

C. They are elementary particles and cannot be broken down

D. They are considerably smaller than neutrons or protons

1

DH

Dương Hoàn Anh

22 tháng 9 2018

Đáp án là A

Theo bài đọc, tất cả những ý nào sau đây đúng về electron NGOẠI TRỪ

A. Mức năng lượng của chúng là cố định và không đổi.

B. Chúng được giữ trong quỹ đạo bởi những lực hấp dẫn mang điện cực.

C. Chúng là những phân tử cơ bản và không thể bị phá vỡ

D. Chúng nhỏ hơn rất nhiều so với các notron và proton.

Dẫn chứng:

They are bound to their atoms through electromagnetic attraction. =>loại B

Electrons are different from neutrons in that they cannot be broken down into smaller particles. => loại C và D

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade...

LQ

Lê Quỳnh Anh

20 tháng 12 2018

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun .In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than of the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas .This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers; their atomic number , which is equal to the number of protons they have, and their atomic weight , which is equal to total number of their neutrons and protons. In most lighter atoms , the number of neutrons and protons is equal , and the element is stable. In heavier atoms, however, there are more neutrons than protons , and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbit. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electron than the previous shell. Electrons naturally seek to occupy the lowest shell possible .So if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light .This is why fires and other very hot objects seem to glow.

Electrons are also primarily responsible for many of the chemical properties of atoms. Since electrons seek to occupy the lowest electron shell possible, they will move from one atom to another if there is a space available in a lower electron shell. For example, if there is an atom with an open space in its third shell, and it comes into contact with an atom with electrons in its fourth shell, the first atom will take one of these electrons to complete its third shell. When this happens, the two atoms will be chemically bonded to form a molecule. Furthermore, atoms sometimes lose electrons in collisions with other atoms. When it happens, the radio of protons and electrons in the atom changes, and therefore, the overall electrical charge of the atom changes as well. These atoms are called isotopes, and they have significantly different chemical properties from their parent atoms.

According to the information in paragraph 2, what will happen if an atom has more neutrons than protons?

A. It will not have enough of a positive electrical charge to keep its electrons in orbit

B. Its nucleus will explode in a supernova

C. It will slowly give off neutrons until the atom becomes stable

D. Its extra neutrons will be converted into light energy

1

DH

Dương Hoàn Anh

20 tháng 12 2018

Đáp án là C

Theo thông tin ở đoạn 2, điều gì sẽ xảy ra nếu 1 nguyên tử có nhiều notron hơn proton?

A. Nó sẽ không có đủ điện cực dương để giữ các electron theo đúng quỹ đạo.

B. Hạt nhân của nó sẽ nổ ở dạng một siêu tân binh.

C. Nó sẽ mất dần notron cho đến khi nguyên tử trở nên cân bằng.

D. Những notron thừa sẽ bị chuyển đổi thành năng lượng ánh sáng.

Dẫn chứng: In heavier atoms, however, there are more neutrons than protons , and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reacheD

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade...

LQ

Lê Quỳnh Anh

23 tháng 4 2017

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun .In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than of the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas .This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers; their atomic number , which is equal to the number of protons they have, and their atomic weight , which is equal to total number of their neutrons and protons. In most lighter atoms , the number of neutrons and protons is equal , and the element is stable. In heavier atoms, however, there are more neutrons than protons , and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbit. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electron than the previous shell. Electrons naturally seek to occupy the lowest shell possible .So if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light .This is why fires and other very hot objects seem to glow.

Electrons are also primarily responsible for many of the chemical properties of atoms. Since electrons seek to occupy the lowest electron shell possible, they will move from one atom to another if there is a space available in a lower electron shell. For example, if there is an atom with an open space in its third shell, and it comes into contact with an atom with electrons in its fourth shell, the first atom will take one of these electrons to complete its third shell. When this happens, the two atoms will be chemically bonded to form a molecule. Furthermore, atoms sometimes lose electrons in collisions with other atoms. When it happens, the radio of protons and electrons in the atom changes, and therefore, the overall electrical charge of the atom changes as well. These atoms are called isotopes, and they have significantly different chemical properties from their parent atoms.

According to paragraph 2, an atom’s atomic number is determined by

A. The sum of its protons and electrons

B. The different in the mass of its neutrons and protons

C. The strength of the bond between its protons and neutrons

D. The total number of protons it has

1

DH

Dương Hoàn Anh

23 tháng 4 2017

Đáp án là D

Theo đoạn 2, số nguyên tử của một nguyên tử được xác định bởi

A. Tổng các hạt proton và electron

B. Số lượng notron và proton khác nhau.

C. Sức mạnh kết hợp giữa các hạt proton và notron.

D. Tổng số proton mà nó có.

Dẫn chứng: Elements are defined by two numbers; their atomic number , which is equal to the number of protons they have