Workshop CHE 166
Problem Set #4
1. Write the balanced chemical equation which corresponds to each of the following descriptions:
a) boron sulfide, B2S3 (s), reacts violently with water to form dissolved boric acid, H3BO3, and hydrogen sulfide gas,
b) when hydrogen sulfide gas is passed onver solid hot iron(III) hydroxide, the resultant reaction produces solid iron(III) sulfide and gaseous water,
c) when ammonia gas, NH3 (g), is passed over hot liquid sodium metal, hydrogen gas is released and sodium azide, NaN3, is formed as a solid product,
d) copper metal reacts with hot concentrated sulfuric acid to form aqueous copper(II) sulfate, sulfur dioxide gas and water,
e) phosphine, PH3 (g), combusts in oxygen gas to form gaseous water and solid tetraphosphorus decaoxide.
2. For the following equations, name each reactant and product and then balance the equation using only integer coefficients:
a) ___ N2O5 (g) + H2O (l) ® ___ HNO3 (aq)
b) ___ (NH4)2Cr2O7 (s) ® ___ N2 (g) + ___ Cr2O3 (s) + ___ H2O (l)
c) ___ PCl3 (l) + ___ H2O (l) ® ___ H3PO3 (aq) + ___ HCl (aq)
d) ___ Mg3N2 (s) + ___ HCl (aq) ® ___ MgCl2 (aq) + ___ NH4Cl (aq)
e) ___ C6H6 (l) + ___ O2 (g) ® ___ CO2 (g) + ___ H2O (l)
f) ___ NCl3 (aq) + ___ H2O (l) ® ___ NH3 (aq) + ___ HOCl (aq)
g) ___ Fe(OH)3 (s) + ___ H2SO4 (aq) ® ___ Fe2(SO4)3 (aq) + ___ H2O (l)
h) ___ C6H22O11 (aq) + ___ O2 (g) ® ___ CO2 (g) + ___ H2O (l)
i) ___ NH3 (g) + ___ O2 (g) ® ___ NO (g) + ___ H2O (g)
j) ___ Pb(NO3)2 (s) ® ___ PbO (s) + ___ NO2 (g) + ___ O2 (g)
k) ___ Ca3P2 (s) + ___ H2O (l) ® ___ Ca(OH)2 (aq) + ___ PH3 (g)
l) ___ PF3 (g) + ___ XeF4 (s) ® ___ PF5 (g) + ___ Xe (g)
m) ___ CaC2 (s) + ___ H2O (l) ® ___ Ca(OH)2 (s) + ___ C2H2 (g)