The light-stimulated conversion of 11-cis-retinal to 11-trans-retinal is central to the vision process in humans. This reaction also occurs (more slowly) in the absence of light. At 80.0 ∘C in heptane solution, the reaction is first order with a rate constant of 1.02×10−5/s. How many hours does it take for the concentration of 11-trans-retinal to reach 3.14×10−3 M ? (Note: 11-cis-retinal + 11-trans-retinal = total amount of retinal in eye)

There are 6.022 x 10^23 atoms of hg in 1 mole of hg. the number of atoms in 4.5 moles of hg can be found by multiplying 4.5 by 6.022 x 10^23 a. 2.7 x 10^24 b. 27 x 10^23 c. 2.71 x10^24 d. 27.099 x 10^23

What happens to the average kinetic energy of a gas when the particles of the gas collide against each other at a constant temperature and volume? explain your answer.

Air pressure is measured in pascals. for a professional american football game, the ball should be inflated to about 90,000 pascals. scientists studied the effects of air temperature on the pressure inside american footballs by taking these steps: 1. prepare 100 footballs. 2. measure each football's air pressure. 3. divide footballs into 10 groups. 4. place the groups in different lockers cooled to different air temperatures. 5. after 12 hours, remove the footballs from lockers. 6. measure each football's pressure again. 7. compare the new pressures to the starting pressures. what two terms best describe the variable "air pressure inside the football" in this experiment? independent, qualitative independent, quantitative dependent, qualitative dependent, quantitative