Question

can someone help me with stoichoimetry?
I have a test tomorrow and I just need some clearing up'

Answer 1

question?

Answer 2

moles to grams
grams to moles
molecules
avogrado's number

Answer 3

Avogadro's number determines the quantity of particles present in 24litres in a system (air, liquid, solid), that is 6.02*10^23, that can be ions, charges, atoms, etc.
For your 1st and 2nd points use the formula: mol=mass/molar mass, and for whichever quantity you want, make it as the subject of the formula.

Answer 4

Molecules are the number of times that an element or a compound exists repeteadly in a system or reaction.

Answer 5

4 NH3 +3 O2--> 2 N2 + 6 H2O

7. if there are 12.9 moles of nitrogen gas produced in the reaction, how many moles of oxygen gas was reacted to produce this amount of nitrogen gas?

8. How many grams of nitrogen gas was produced in question 7?

Answer 6

7. Work with molar ratio, which is determined in your reaction.
As you can see, it is 3:2 or 1.5:1, therefore if you have 12.9mol of N2, then you have 12.9*1.5/1=19.35mol of O2.

Answer 7

Use the formula mol=mass/molar mass, then mass=molar mass*mol or 28*19.35

Answer 8

thx

Answer 9

Right.

Answer 10

No.