Question

1. Which of the following properties are physical?

Boiling point, density, flammable, color, liquid at 25oC, odor

2. Determine the oxidation number for each of the following:

a. S in H2SO3

b. Cl in NaClO3

c. C in H2C2O4

Answer 1

A)

Boiling point --> no chemical change, only phase change, therefore physical

B)

density --> no change in chemical composition, therefore physical property

C)

flammable --> chemical property, since it changes chemical composition

d)

color --> no chemical chang,e therefore physcal property

e)

liquid at 25oC --> physcal property, no change in chemica composition

f)

odor --> physcal property

Q2

S --

2H + S + O3 = 0

2(1) + S + (-2)*3 = 0

S = +6-2 = +4

S = +4

B)

Na + Cl + 3O = 0

+1 + Cl + 3(-2) = 0

Cl = +6-1 = +5

c)

C in

H2C2O4

2H + 2C + 4O = 0

2(1) +2C + 4(-2) =

C = (8 - 2 )/2

C = +3