14. How old is a piece of cotton cloth if the half-life of carbon-14 is 5,730 years, and the carbon-14 composition of the cloth is 22 percent that living plants? A. 1.21 * 10^-4 years^-1
B. 1.21 * 10^-4 years
C. 1,813 years
D. 12,517 years

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.

How does a catalyst increase the speed of a reaction? a. the catalyst eliminates the activated complex stage, allowing products to form immediately. b. the catalyst lowers the energy level of the reactants, making it easier for them to react. c. the catalyst makes it easier for the activated complex to form, lowering the activation energy. d. the catalyst raises the energy level of the products, making the reaction finish sooner. reset next

Δu of , in kj/kg, as it isto k, (a)as a of , (b) at , (c) at .