Answer:

Explanation:
First reaction gives you the number of moles or the mass from Carbon and hydrogen
for carbon:


Analogously for hydrogen:
0.0310g
have 0.0034gH or 0.0034mol of H
In the second reaction you can obtain the amount of nitrogen as a percentage and find the mass of N in the first sample.

now

this is equivalet to 0.002mol of N
with this information you can find the mass of oxygen by matter conservation.

this is equivalent to 0.004molO
finally you divide all moles obtained between the smaller number of mole (this is mol of H)

and you can multiply by 5 to obtain: 
Answer:
134K
Explanation:
Using the ideal gas law equation;
PV = nRT
Where;
P = pressure (atm)
V = volume (Litres)
n = number of moles (mol)
R = gas constant (0.0821 Latm/Kmol)
T = temperature (K)
Based on the information provided, n = 1.4moles, P = 3.25atm, V = 4.738L, T = ?
3.25 × 4.738 = 1.4 × 0.0821 × T
15.3985 = 0.11494T
T = 15.3985/0.11494
T = 133.969
Approximately;
T = 134K
Is air a compound mixture or a element. compound
Density is Mass divided by volume.