CHE EXAM #1 (2025/26) QUESTIONS & ANSWERS.
A substance that cannot be purified further by normal physical means.
However, when an electric current is sent through the substance between two
electrodes, a metal forms around one electrode and a gas is produced by the
other electrode. This substance is most likely:
homogeneous mixture
element
compound
heterogenous mixture Answer - compound
Which one is a chemical property?
color
density
melting
flammability
electrical conductivity Answer - flammability
How many pL are in 5.0 × 10^2 nL?
5.0 × 10^−1 pL
5.0 × 10^1 pL
5.0 × 10^3 pL
5.0 × 10^2 pL Answer - 5.0 × 10^−1 pL
What is the result of the following calculation
, 6.48x10^5/(2.4x10^4) x (1.8x10^-2)?
1.5 × 10^3
1.5 ×10^2
1.5 × 10^4
15
1.5 Answer - 1.5 × 10^3
What is the density of an unknown element, in g/mL, where 102 g occupies
3.47 x 10^−3 liters of space?
29.4 g/mL
3.40 × 10^−5 g/mL
2.94 × 10^4 g/mL
0.0341 g/mL Answer - 2.94 × 10^4 g/mL
How many significant figures does 10.54020 have?
6
4
3
5
7 Answer - 7
What is the answer, rounded to correct significant figures, of: 64/5×3.5 =
4.4 × 10^1
4.48 × 10^1
4
4 × 10^1 Answer - 4×10^1
A substance that cannot be purified further by normal physical means.
However, when an electric current is sent through the substance between two
electrodes, a metal forms around one electrode and a gas is produced by the
other electrode. This substance is most likely:
homogeneous mixture
element
compound
heterogenous mixture Answer - compound
Which one is a chemical property?
color
density
melting
flammability
electrical conductivity Answer - flammability
How many pL are in 5.0 × 10^2 nL?
5.0 × 10^−1 pL
5.0 × 10^1 pL
5.0 × 10^3 pL
5.0 × 10^2 pL Answer - 5.0 × 10^−1 pL
What is the result of the following calculation
, 6.48x10^5/(2.4x10^4) x (1.8x10^-2)?
1.5 × 10^3
1.5 ×10^2
1.5 × 10^4
15
1.5 Answer - 1.5 × 10^3
What is the density of an unknown element, in g/mL, where 102 g occupies
3.47 x 10^−3 liters of space?
29.4 g/mL
3.40 × 10^−5 g/mL
2.94 × 10^4 g/mL
0.0341 g/mL Answer - 2.94 × 10^4 g/mL
How many significant figures does 10.54020 have?
6
4
3
5
7 Answer - 7
What is the answer, rounded to correct significant figures, of: 64/5×3.5 =
4.4 × 10^1
4.48 × 10^1
4
4 × 10^1 Answer - 4×10^1
