Intensive Set Chapter 2
Basic
1. If an atom contains 16 protons and 18 neutrons, what is its mass number? Write the
shorthand representation for that atom and name it.
2. If a neutral atom has a mass number of 13 and an atomic number of 6, how many
protons, neutrons, and electrons are in that atom? Write the shorthand representation
for that atom and name it
3. Natural oxygen consists of 99.76% 16O (15.9949 u), 0.0400% 17O (16.9991 u) and
0.02000% 18O (17.9992 u). What is the average atomic mass of oxygen?
4. Calculate the average atomic mass of magnesium. Magnesium consists of three
isotopes: 24Mg = 23.985 u with a percent abundance of 78.99%, 25Mg = 24.986 u
with a percent abundance of 10.00%, the rest is 26Mg = 25.983 u.
5. Write the molecular and empirical formulas of each of the following compounds:
a. an organic compound, heptanol, has 7 carbon atoms , 16 hydrogen atoms, and 1
oxygen atom
b. Vitamin C, ascorbic acid, has six carbon atoms, eight hydrogen atoms, and six
oxygen atoms
c. Aspartane, an artificial sweetener, has 14 carbon atoms, 18 hydrogen atoms, and 5
oxygen atoms
6. Give the total number of atoms in TNT, C6H2CH3(NO2)3 and in Ge[S(CH2)4CH3]4.
7. Which of the following are correct formulas for ionic compounds? For those that are
not, give the correct formula.
a. Ca2O
b. SrBr2
c. Li2O
8. Write formulas for the ionic compounds that can be formed by combining the cations,
NH4+, Ni+2 with the anions CO3-2, SO4-2.
9. Give an example of each of the following:
a. halogen
b. transition metal
c. noble gas
d. nonmetal
e. lanthanide
f. alkaline earth metal
g. actinide
