A Concentration-Time Study of the Gas Phase Reaction 2 A₃

question 63

Multiple Choice

A concentration-time study of the gas phase reaction 2 A₃ → 3 A₂ produced the data in the table below. Time (s) [A₃] (M) [A₂] (M)
0 4.00 × 10^-4 0
10 2.00 × 10^-4 3.00 × 10^-4
20 1.00 × 10^-4 4.50 × 10^-4
30 5.00 × 10^-5 ?
What is the concentration of A₂ after 30 seconds?

• A)5.00 × 10^-4 M
• B)5.25 × 10^-4 M
• C)5.50 × 10^-4 M
• D)6.00 × 10^-4 M

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Definitions:

Ozone Layer

A layer in the earth's stratosphere containing a high concentration of ozone, which absorbs most of the sun's ultraviolet radiation.

Ice Crystals

Water molecules in the solid state that manifest in symmetrical patterns, typically forming under low temperature conditions in the atmosphere or on surfaces.

Southern Hemisphere

The half of Earth that lies south of the equator, encompassing parts of South America, Africa, Australia, and Antarctica.

CFCs

stands for chlorofluorocarbons, which are compounds previously used in aerosols, refrigerants, and foam blowing agents that contribute to ozone layer depletion.