1. A Review of General Chemistry

Chlorine exists as one of two isotopes with atomic masses of 34.969 amu (³⁵Cl) and 36.966 amu (³⁷Cl) . Calculate the relative abundance of ³⁵Cl and ³⁷Cl based on the average atomic mass of 35.453 amu.

Bromine-79 (50.7% abundance) has an atomic mass of 78.918 amu, whereas bromine-81 (49.3% abundance) has an atomic mass of 80.916 amu. From these data, calculate the average atomic mass of bromine that you would expect to see in the periodic table.

A chemistry student drew the following incorrect electron configuration for carbon. (b) Which rule wasn't followed by the student?

Give the electron configuration of the following elements.

(d) F

Why do elements in the same group of the periodic table display similar reactivity?

Choose the larger atom in each pair.

(d) N or S

Give the electron configuration of the following elements.

(c) O

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

(a) Beryllium

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?

(a) Oxygen

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?

(c) Phosphorus

A chemistry student drew the following incorrect electron configuration for carbon. (a) Correct the diagram.

Would you expect electrons in the 2s or 3s orbital to be more reactive? Why?

What is the ground state electron configuration of carbon? How many bonds does carbon usually form?

In the periodic table, the number 79.904 appears under the element bromine. What is the significance of this number?

Choose the larger atom in each pair.

(b) O or F