HW #5

2SCS #1-12 

1. The law of conservation of matter is that matter is neither created nor destroyed.

2. Laws that describe the behavior of events in nature, but they do no provide explanations for the observed behavior.

3. They are misleading because based on the law of conservation of matter; atoms are not "used up" or "thrown away." Atoms can’t be destroyed.

4. 

(a) Not balanced; Reactant side: Sn, 1; H, 1; F, 1; Product side: Sn, 1; H, 2; F; 2

(b) Not balanced; Reactant side: Si, 1; O, 2; C, 1; Product side: Si, 1; O, 1; C, 2

(c) Balanced; Reactant side: Al, 1; O, 3; H, 6; Cl, 3; Product side: Al, 1; O, 3; H, 6; Cl, 3

5. (a) 3     (b) 2     (c) 1

6. 

(a)   1, 3, 1 ,3

(b)  2, 3, 2, 2

(c)   4, 2, 3

7. 

(a) 1 Ca3(PO4)2 + 3 H2SO4 --> 2 H3PO4 + 3 CaSO4

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

8. (a) yes

 Reactant: Na-2                  Product: Na-2

                        S-1                                    S-1

                        O-4                                   O-4

                        K-2                                   K-2

                        Cl-2                                  Cl-2

(b) No, because subscripts always stay the same and coefficients change to balance equations.

(c) 1, 2, 1, 2

9. It would take 400,000 moles to spend a billion dollars.

10. 
(a) 32 g

(b) 48 g

(c) 100 g

(d) 58 g

(e) 180 g

11. Atomic mass equals atomic weight and the weight always stays the same.

12. 
(a) 1 atom

(b) 0.5 atoms

(c) 0.1 atoms

(d) 0.03 atoms