1. A Review of General Chemistry

How many electrons does an atom of each of the following elements need to gain to achieve a noble gas configuration? By gaining that many electrons, which noble gas configuration is achieved?

(b) Iodine

PRACTICE: Determine the number of protons, neutrons and electrons in the following atoms.

PRACTICE: Determine the number of protons, neutrons and electrons in the following atoms.

PRACTICE: Determine which of the three principles of electron configuration is being broken in the electron diagrams below.

PRACTICE: Determine which of the three principles of electron configuration is being broken in the electron diagrams below.

Nitrogen has relatively stable isotopes (half-life greater than 1 second) of mass ­numbers 13, 14, 15, 16, and 17. All except ¹⁴N and ¹⁵N are radioactive.) Calculate how many protons and neutrons are in each of these isotopes of nitrogen.

Draw the ground-state electronic configuration for each of the following:

b. Ca²⁺

Draw the ground-state electronic configuration for each of the following:

a. Mg

Chlorine has two isotopes, ³⁵Cl and ³⁷Cl; 75.77% of chlorine is ³⁵Cl, and 24.23% is ³⁷Cl. The atomic mass of ³⁵Cl is 34.969 amu, and the atomic mass of ³⁷Cl is 36.966 amu. What is the atomic mass of chlorine?

Name the element that corresponds to each electronic configuration.

a. 1s² 2s² 2p²

b. 1s² 2s² 2p⁴

c. 1s² 2s² 2p⁶ 3s² 3p³

d. 1s² 2s² 2p⁶ 3s² 3p⁵

Write the ground-state electronic configuration for chlorine (atomic number 17), bromine (atomic number 35), and iodine (atomic number 53).

Oxygen has three isotopes, ¹⁶O, ¹⁷O, and ¹⁸O. The atomic number of oxygen is 8. How many protons and neutrons does each of the isotopes have?

a. How many protons do the following species have?

b. How many electrons does each have?

1. Na⁺
2. Ar
3. Cl^-

Write the electronic configurations of the third-row elements shown in the partial ­periodic table in Figure 1-6.