C.1-C.7

1. State the law of conservation of matter.

THat matter can not be destroyed of made

2. What is a scientific law?

3.Why are expressions such as "using up" and "throwing away" misleading, if the law of conservation of matter is taken into account?

Materials are being chemically changed, not destroyed .

4. a.not balanced

b.not balanced 

c.not balanced

5..a3

b.2

c.2

6.

1WO3 + 3H2---> 1W + 3H2O

b.1PbS + 2O2------> 2PbO + 1SO2

c.2fe+3O2---> 2Fe2O3

7.1Ca8H18+ 1O2-->2H3PO4 + 3CaSO4

b.2C8H18 + 25 O2----> 16CO2 + 18H2O

8.a Na:2

SO:4

NaCl:1

K:2

SO:4

b.yes

9.help

10.

a. 32g

b48g

c.100g

d.58g

e.172g

11. Balance the equations

12. Help!