1.
Protons are located in the nucleus of the atom. A proton has:
Correct Answer
D. A positive charge
Explanation
Protons are positively charged particles that are found within the nucleus of an atom. They have a fundamental unit of positive charge, which is equal in magnitude to the negative charge of an electron. This positive charge of protons is essential for the overall stability and structure of an atom.
2.
Neutrons are in the nucleus of the atom. A neutron has:
Correct Answer
B. No charge
Explanation
Neutrons are electrically neutral particles, meaning they have no charge. Unlike protons, which have a positive charge, and electrons, which have a negative charge, neutrons do not possess any electrical charge. They are found in the nucleus of an atom along with protons, and their main role is to stabilize the nucleus by balancing the repulsive forces between positively charged protons.
3.
An electron is in a region outside the nucleus. An electron
Correct Answer
B. Has less mass than a proton and has a negative charge
Explanation
An electron is a subatomic particle that orbits around the nucleus of an atom. It is much smaller in size compared to a proton and has a negative charge. Additionally, electrons have significantly less mass than protons. Therefore, the correct answer is "Has less mass than a proton and has a negative charge."
4.
A hydrogen atom is made up of one proton and one electron. The proton and electron stay near each other because:
Correct Answer
C. Positive and negative charges attract
Explanation
The correct answer is that positive and negative charges attract. This is because the proton has a positive charge and the electron has a negative charge. According to the fundamental principle of electrostatics, opposite charges attract each other. Therefore, the positive charge of the proton and the negative charge of the electron create an attractive force that keeps them near each other in the hydrogen atom.
5.
The atomic number of an atom is:
Correct Answer
C. The number of protons
Explanation
The atomic number of an atom refers to the number of protons in the nucleus of the atom. It is a unique identifier for each element and determines its place in the periodic table. The mass of the atom is determined by the combined mass of protons, neutrons, and electrons, but the atomic number specifically refers to the number of protons. The number of protons also determines the overall charge of the atom, as it is balanced by an equal number of electrons in a neutral atom. Therefore, the correct answer is "The number of protons."
6.
The atoms of the same element can have different isotopes. An isotope of an atom:
Correct Answer
B. Is an atom with a different number of neutrons
Explanation
Isotopes are atoms of the same element that have different numbers of neutrons. The number of protons in an atom determines its atomic number and identifies the element, while the number of neutrons can vary among isotopes of the same element. Therefore, an isotope is an atom with a different number of neutrons.
7.
The atomic mass of an element is:
Correct Answer
A. The average mass of all the isotopes of the element
Explanation
The atomic mass of an element is the average mass of all the isotopes of the element. Isotopes are atoms of the same element that have different numbers of neutrons, resulting in different atomic masses. The atomic mass takes into account the abundance of each isotope and calculates the weighted average. This is important because it provides a more accurate representation of the element's mass than just considering the most common isotope.
8.
An element and an atom are different but related because:
Correct Answer
C. An element is made up of all the same type of atom
9.
The periodic table shows that a carbon atom has six protons. This means that a carbon atom also has:
Correct Answer
A. Six electrons
Explanation
A carbon atom has six protons, which is its atomic number. The atomic number determines the number of electrons in an atom, so a carbon atom also has six electrons. Protons have a positive charge, while electrons have a negative charge, and in a neutral atom, the number of protons is equal to the number of electrons. Therefore, a carbon atom has six protons and six electrons.
10.
The atomic number of nitrogen is 7. The atomic mass is 14.01. This means that:
Correct Answer
C. A small percentage of nitrogen atoms have more than 7 neutrons
Explanation
The atomic number of an element represents the number of protons in the nucleus of an atom. In the case of nitrogen, the atomic number is 7, indicating that there are 7 protons. The atomic mass of an element is the sum of the number of protons and neutrons in the nucleus. Since the atomic mass of nitrogen is 14.01, it means that on average, nitrogen atoms have 7 neutrons. However, the atomic mass is not a whole number, which suggests that there are different isotopes of nitrogen with varying numbers of neutrons. Therefore, a small percentage of nitrogen atoms may have more than 7 neutrons.
11.
Electrons are in regions around the nucleus called energy levels. The first energy level:
Correct Answer
B. Is closest to the nucleus
Explanation
The first energy level is closest to the nucleus because energy levels are arranged in increasing distance from the nucleus. As electrons fill up the energy levels, they occupy the closest level first before moving to the next level further away. Therefore, the first energy level is the one that is closest to the nucleus.
12.
Neon has 10 protons and 10 electrons. The electrons fill the energy levels in Neon like this:
Correct Answer
A. 2 in the first, 2 in the second, and 6 in the third
Explanation
Neon, with its atomic number of 10, has an electron configuration of 1s² 2s² 2p⁶. In the first energy level, the 1s subshell accommodates 2 electrons, while the second energy level is comprised of a fully filled 2s subshell with 2 electrons and a fully filled 2p subshell with 6 electrons. This arrangement results in a stable configuration for neon, contributing to its inert and non-reactive nature as a noble gas.
13.
The atoms in a column of the periodic table all have:
Correct Answer
D. The same number of electrons
Explanation
The correct answer is that the atoms in a column of the periodic table all have the same number of electrons. This is because elements in the same column, also known as a group or family, have similar chemical properties, which are primarily determined by the number of electrons in their outermost energy level. Therefore, atoms in the same column have the same number of valence electrons, leading to similar chemical behavior.
14.
In the process of covalent bonding, atoms share electrons. This means that:
Correct Answer
A. Electrons from each atom are attracted to the nucleus of both atoms
Explanation
In covalent bonding, atoms share electrons, which means that the electrons from each atom are attracted to the nucleus of both atoms. This attraction occurs because the positively charged protons in the nucleus attract the negatively charged electrons. This sharing of electrons allows both atoms to achieve a more stable electron configuration, resulting in a stronger bond between the atoms.
15.
In the process of ionic bonding:
Correct Answer
B. One atom gains one or more electrons and the other loses the same numbe
Explanation
In the process of ionic bonding, one atom gains one or more electrons and the other loses the same number. This occurs because one atom has a higher electronegativity, or attraction for electrons, than the other atom. The atom with higher electronegativity gains electrons to achieve a stable electron configuration, becoming negatively charged. The atom with lower electronegativity loses electrons, resulting in a positive charge. This transfer of electrons creates ions with opposite charges, which are then attracted to each other and form an ionic bond.
16.
Different atoms of the same element can have a different number of ________
Correct Answer
neutrons
Explanation
Atoms of the same element can have a different number of neutrons. Neutrons are subatomic particles that have no charge and are found in the nucleus of an atom. The number of neutrons in an atom can vary, resulting in different isotopes of the same element. Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons. The variation in the number of neutrons affects the atomic mass of the element, but not its chemical properties.
17.
The atomic number of an atom is equal to the number of ________ in the atom's nucleus.
Correct Answer
protons
Explanation
The atomic number of an atom is equal to the number of protons in the atom's nucleus. Protons are positively charged particles found in the nucleus of an atom. Each element on the periodic table has a unique atomic number, which corresponds to the number of protons in its nucleus. Therefore, the atomic number provides important information about the identity and properties of an element.
18.
When an atom loses an electron, it forms a ________ ion.
Correct Answer
positive, Positive, Cation, cation
Explanation
When an atom loses an electron, it forms a positive ion. This is because when an atom loses an electron, it becomes positively charged since it now has more protons than electrons. This positive ion is called a cation and it is attracted to negatively charged particles.
19.
When an atom gains an electron, it forms a ________ ion.
Correct Answer
negative
Explanation
When an atom gains an electron, it forms a negative ion. This is because the electron that is gained has a negative charge, causing the overall charge of the atom to become negative.
20.
In a covalent bond, electrons are ________ between two atoms.
Correct Answer
shared
Explanation
In a covalent bond, electrons are shared between two atoms. This means that the electrons are not completely belonging to one atom or the other, but rather they are shared and occupy the space between the two atoms involved in the bond. This sharing of electrons allows both atoms to achieve a more stable electron configuration, resulting in a stronger bond between them.
21.
When an atom loses an electron, it forms a ________ ion.
Correct Answer
positive
Explanation
When an atom loses an electron, it forms a positive ion. This is because when an atom loses an electron, it becomes positively charged. The loss of negatively charged electrons leaves the atom with a net positive charge, resulting in the formation of a positive ion.