[pinkemistry]

Please help me with these problems and show all work. Thanks in advance.
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What is the ratio used to carry out each conversion?
  a.)mol CH4 to gram CH4
  b.)L CH4 (g) to mol CH4 (g) at STP
  c.)molecules CH4 to mol CH4
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The combustion of acetylene gas is represented by this equation:
2C2H2(g) + 5O2(g)------------>4CO2(g) + 2H2O(g)

a.   How many grams of CO2 and grams of H2O are produced when 52.0g C2H2 burns?
b.   How many grams of oxygen are required to burn 52.0g C2H2?
c.   Use the answers from a and b to show that the law of conservation of mass was obeyed.
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Tin(II) fluoride, formerly found in many kinds of toothpaste, is formed in this reaction”
Sn(s) + 2HF(g)----------->SnF2 (s) + H2 (g).

a.   How many liters of HF are needed to produce 9.40 L H2 at STP?
b.   How many molecules of H2 are produced by the reaction of tin with 20.0 L HF at STP?
c.   How many grams of SnF2 can be made by reacting 7.42 X 10²⁴ molecules of HF with tin?

[mike]

Please help us by attempting these questions first and showing us all of your working. Thanks in advance.

[pinkemistry]

I  cant attemp the problems because i do not know how to do them

[mike]

For question 1:

n = m/M     where n = moles, m = mass, and M = molecular weight

PV = nRT    where P = pressure, V = volume, R = gas constant, T = temperature

Avagadro