B.
The cynobacteria were already there without the oxygen, so that rules out A, and a lot of prokaryotes were anaerobic, so that rules out C. Finally, Photosynthesis does not require oxygen. Instead, Oxygen is a waste product of it. Therefore, it cannot be D. So, we are only left with B
Hoped this helped :D
Answer:
nitrogen dioxide
Explanation:
this was on my chemistry test
Answer:
How many moles Al(NO3)3 in 1 grams? The answer is 0.0046949186022713.
We assume you are converting between moles Al(NO3)3 and gram.
You can view more details on each measurement unit:
molecular weight of Al(NO3)3 or grams
This compound is also known as Aluminium Nitrate.
The SI base unit for amount of substance is the mole.
1 mole is equal to 1 moles Al(NO3)3, or 212.996238 grams.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between moles Al(NO3)3 and gram.
Type in your own numbers in the form to convert the units!
Explanation:
Answer: D. The number of molecules having Er or greater doubles.
Explanation: As the temperature increases from 20°C to 30°C, the number of molecules with maximum energy decreases, but the number of effective collisions which result into the formation of product doubles.
This is due to doubling of molecules which possess energy equal to or greater than 
which means now double number of molecules will be able to cross the energy barrier and hence the formation of product increases and hence the rate increases to double.
