Question

q 1.13 an atom that gains electrons becomes a ______

a cation
b isotope
c neutral atom
d anion

q 1.14 the atomic number of an element represents the number of ______

a neutrons
b protons
c isotopes
d shells

q 1.15 elements in the same group on the periodic table have similar ______

a masses
b physical sizes
c chemical properties
d numbers of neutrons

q 1.16 why do elements form chemical bonds?

a to lose all electrons
b to gain neutrons
c to achieve a full valence shell
d to decrease mass

Explanation:

Analyze Q 1.13: Ion formation

An atom that gains electrons acquires a negative charge because electrons are negatively charged subatomic particles. A negatively charged ion is called an anion.

Analyze Q 1.14: Atomic number definition

The atomic number of an element is defined as the number of protons in the nucleus of an atom of that element.

Analyze Q 1.15: Periodic table groups

Elements in the same vertical column (group) of the periodic table have the same number of valence electrons, which gives them similar chemical properties.

Analyze Q 1.16: Purpose of chemical bonding

Atoms form chemical bonds to achieve a stable electron configuration, which typically means having a full outer (valence) shell of electrons.

Answer:

Question 1.13

• A cation
• B isotope
• C neutral atom
• D anion (Correct answer)

Question 1.14

• A neutrons
• B protons (Correct answer)
• C isotopes
• D shells

Question 1.15

• A masses
• B physical sizes
• C chemical properties (Correct answer)
• D numbers of neutrons

Question 1.16

• A To lose all electrons
• B To gain neutrons
• C To achieve a full valence shell (Correct answer)
• D To decrease mass