A Gas-Phase Decomposition Is First-Order with Respect to the Reactant

question 59

Multiple Choice

A gas-phase decomposition is first-order with respect to the reactant, R. If the initial concentration of R is 1.0 *¯⁴ mol L¯¹ and the rate constant k = 1.08 *10¯⁶ s¯¹, what concentration of R remains after 25 days?

• A) 1.0 * 10¯³ mol L¯¹
• B) 1.0 *10¯⁴ mol L¯¹
• C) 9.6 * 10¯⁵ mol L¯¹
• D) 4.3 * 10¯⁵ mol L¯¹
• E) 9.7 *10¯⁶ mol L¯¹

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Definitions:

Contribution Margin

The difference between sales revenue and variable costs, used to cover fixed costs and to provide profit to the company.

Fixed Costs

Expenses that do not change with the volume of production or sales, such as rent, salaries, and insurance.

Variable Costs

Expenditures that adjust based on the quantity of production or the scale of sales.

Utility Rates

Charges imposed by utility companies for the use of services such as electricity, gas, water, and sewer.