11. Which of these conditions would decrease the rate of photosynthesis in a plant? A. above average precipitation

B. Changing the daylight hours from 14 hrs to 10 hrs

C. Changing the CO2 concentration from 380 ppm to 410 ppm

D. All of these choices

Calculate the molar mass of aluminum oxide (al2o3). express your answer to four significant figures.

Suppose a lab group reports a ppercent yield of sand of 105. is it really possible to collect more sand than was originally represented? what is the possible explanation for the extra product?

16. why must the number of electrons lost equal the number of electrons gained in every redox reaction? use 3 – 4 sentences in your own words to address this question. 18. what type of radiation is emitted when chromium-51 decays into manganese-51? show the nuclear equation that leads you to this answer. 19. a radioactive nucleus alpha decays to yield a sodium-24 nucleus in 14.8 hours. what was the identity of the original nucleus? show the nuclear equation that leads you to this answer.