CHEM-121_Written Assignment 4 - Thomas Edison State College...

Thomas Edison State College
General Chemistry I with Labs (CHE-121)
Section no.: OL009
Semester and year: Feb2015
Written Assignment 4: Chemical Reactions
Answer all assigned questions and problems, and show all work.
1 Write the (a) balanced equation for the formation of liquid water from hydrogen and oxygen
gas, and use it to explain the following terms: (b) chemical reaction, (c) reactant, (d)
product. (12 points)
a 2H
2
+ O
2
→ 2H
2
O
b Chemical reaction: hydrogen gas and oxygen are burned to form water
c Reactant H
2
and O
2
d Product: H
2
O
2 Balance the following equations: (18 points)
a 2C + O
2
→ 2CO
b 2CO + O
2
→ 2CO
2
c 2Na + 2H
2
O → H
2
+ 2NaOH
d Zn + 2HCl → ZnCl
2
+ H
2
e 2NaOH + H
2
SO
4
→ 2H
2
O + Na
2
SO
4
f 2NH
3
+ 3CuO → 3Cu + N
2
+ 3H
2
O
3 Calculate the mass in grams of iodine (I
2
) that will react completely with 20.4 g of
aluminum (Al) to form aluminum iodide (AlI
3
). (5 points)
(Reference: Chang 3.47)
3I
2
+ 2Al → 2AlI
3
(2 x 27.0) g of Al react completely with [3 x (2 x 126.9)] g of I
2
20.4 g of Al will react completely with (761.4 x 20.4) / 54.0 = 287.64 = 288 g of I
2
4 The annual production of sulfur dioxide from burning coal and fossil fuels, auto exhaust,
and other sources is about 26 million tons. The equation for the reaction is
S(s) + O
2
(g) → SO
2
(g)
How much sulfur (in tons), present in the original materials, would result in that quantity of
SO
2
? (5 points)
(Reference: Chang 3.69)

32.1 g of S reacts with O
2
will result of 64.1 g of SO
2
26 x 10
6