Basic Chemistry Review
1. An atom of astatine has an atomic number of 85 and an atomic mass of 210 u.
a) How many protons are there in one atom of astatine?
b) How many electrons are there in one atom of astatine?
c) How many neutrons are there in one atom of astatine?
d) How many protons are there in 10 atoms of astatine?
e) What is the atomic mass of astatine?
f) What is the mass number of astatine?
2. Draw the Bohr diagram for an ion of Si. Which inert gas does the ionic form of Si
most resemble in terms of its electron configuration?
3. A new element has been discovered and all you know is that it is a halogen.
a. Predict the state at room temperature of this new halogen.
b. Predict the number of electrons in its outer orbit.
c. Predict its possible atomic number(s)
d. What do you base your predictions on?
4. Write the formula for the following:
a. iron (II) chloride
b. tin (II) nitride
c. lead (II) oxide
d. dinitrogen trioxide
e. hexasilicon tetrasulfide
5. Write names for the following:
a. CuI2
b. CoO
c. FeBr3
d. B2O3
e. SO2
6. Write word equations for the following:
a. CO2 (g) + H2O (l) --> H2CO3 (aq)
b. AgNO3 (aq) + NaCl (aq) --> AgCl (s) + NaNO3 (aq)
c. C3H8 (g) + 5O2 (g) --> 3CO2 (g) + 4H2O (l)
d. Fe (s) + CuSO4 (aq) --> Cu (s) + FeSO4 (aq)
7. Translate the following word equations into balanced chemical equations.
a. solid sodium metal reacts with gaseous chlorine to produce solid sodium chloride
b. solid platinum (II) oxide decomposes to produce solid platinum and gaseous
oxygen
c. solid gold (I) phosphide reacts with solid calcium sulphide to produce solid gold
(I) sulphide, solid calcium, and gaseous phosphorus.
Solutions
1. a) 85 b) 85 c) 125 d) 850 e) 210 u f) 210
2.
This most resembles the inert gas Ne because Ne also has 10 electrons.
3. A new element has been discovered and all you know is that it is a halogen.
a. Predict the state at room temperature of this new halogen.
The new element will be a gas.
b. Predict the number of electrons in its outer orbit.
The new element will have 7 electrons in its outer orbit.
c. Predict its possible atomic number(s)
The possible atomic numbers are 9,17,35.
d. What do you base your predictions on?
These predictions are based on the periodic nature of elements. The element
would show characteristics of the halogen family.
4. Write the formula for the following:
a. iron (II) chloride
FeCl2
b. tin (II) nitride
Sn3N2
c. lead (II) oxide
PbO
d. dinitrogen trioxide
N2O3
e. hexasilicon tetrasulfide
Si6S4
5. Write names for the following:
a. CuI2
copper (II) iodide
b. CoO
cobalt (II) oxide
c. FeBr3
iron (III) bromide
d. B2O3
diboron trioxide
e. SO2
sulphur dioxide
6. Write word equations for the following:
a. CO2 (g) + H2O (l) --> H2CO3 (aq)
1 molecule of gaseous carbon dioxide reacts with 1 molecule of liquid water
(dihydrogen monoxide) to form 1 molecule of aqueous carbonic acid.
b. AgNO3 (aq) + NaCl (aq) --> AgCl (s) + NaNO3 (aq)
1 formula unit of aqueous silver nitrate reacts with 1 formula unit of aqueous
sodium chloride to form 1 formula unit of solid silver chloride and 1 formula
unit of aqueous sodium nitrate.
c. C3H8 (g) + 5O2 (g) --> 3CO2 (g) + 4H2O (l)
1 molecule of gaseous propane (tricarbon octahydride) reacts with 5 molecules
of gaseous oxygen to produce 3 molecules of gaseous carbon dioxide and 4
molecules of liquid water (dihydrogen monoxide)
d. Fe (s) + CuSO4 (aq) --> Cu (s) + FeSO4 (aq)
1 atom of solid iron reacts with 1 formula unit of aqueous copper (II) s
ulphate to produce 1 atom of solid copper and 1 formula unit of aqueous iron
(II) sulphate.
7. Translate the following word equations into balanced chemical equations.
a. solid sodium metal reacts with gaseous chlorine to produce solid sodium chloride
2Na (s) + Cl2 (g) --> 2NaCl (s)
b. solid platinum (II) oxide decomposes to produce solid platinum and gaseous
oxygen
2PtO (s) --> 2Pt (s) + O2 (g)
c. solid gold (I) phosphide reacts with solid calcium sulphide to produce solid gold
(I) sulphide, solid calcium, and gaseous phosphorus.
2Au3P (s) + 3CaS (s) --> 3Au2S (s) + 3Ca (s) + 2P (g)