Atomic Structure & Nuclear Chemistry Review

An unstable nucleus loses the most mass if the nucleus emits _____.

• an alpha particle

• a beta particle

• a gamma ray

• a neutron

Magnesium has three naturally occurring isotopes in different percent abundance, Mg–24, Mg–25, and Mg–26. Which of the following isotopes would you expect to have the highest percent abundance?

• Mg-24

• Mg-25

• Mg-26

Vanadium comprises two isotopes and has an average atomic mass of 50.9415 amu. V-51 has an abundance of 97%. What is the identity and percent abundance of vanadium’s other isotope? 

• V-49, with an abundance of 3.0%      

• V-50, with an abundance of 3.0%

• V-48, with an abundance of 5.0%

• V-47, with an abundance of 6.0%

Which set of atoms is in the correct order of increasing atomic radii?

• Rb < Na < Li

• Cl < P < S

• He < Ne < Ar

• F < As < Ba

Which grouping of circles, when considered in order from the top to the bottom, best represents the relative size of the atoms of Li, Na, K and Rb, respectively?

• 
• 
• 
• 

The table gives information about the nucleus of each of the four atoms. How many different elements are represented by the nuclei in the table?

• 1

• 2

• 3

• 4

An increase in atomic number is related to an increase in atomic mass because:

• more electrons are present in the atomic nucleus.

• more electrons are orbiting the atomic nucleus.

• more protons are present in the atomic nucleus.

• more protons are orbiting the atomic nucleus.

Which pair of atoms represent nuclei that have the same number of neutrons?

• ⁵⁶Co and ⁵⁸Co

• ⁵⁷Mn and ⁵⁷Fe

• ⁵⁸Ni and ⁵⁷Fe

• ⁵⁸Ni and ⁵⁷Co

Which of the following are examples of everyday uses of nuclear reactions?

1. Food irradiation

2. Medical use of radioactive isotopes

3. A combustion engine

4. A nuclear power plant

5. Smoke detectors

• 1, 2, 3, 4, 5

• 1, 2, 3

• 1, 2, 4, 5

• 1, 2, 3, 4

Rutherford bombarded a gold foil with alpha particles. Most of the particles went straight through the foil, and a few were deflected. Which of these conclusions can be drawn from Rutherford’s experiment?

• An atom is mostly empty space with a dense, positively charged nucleus.

• An atom is composed of at least three types of subatomic particles.

• An electron has a positive charge and is located inside the nucleus.

• An electron has properties of both waves and particles.