To calculate the molecular formula, convert the mass ratio into molar ratio as follows:
mass ratio of O:C=2:1
molar mass of carbon is 12 g/mol and that of oxygen is 16 g/mol thus, number of moles can be calculated as follows:
n=\frac{m}{M}
calculating ratio,
O:C=\frac{2 g}{16 g/mol}:\frac{1 g}{12 g/mol}=\frac{1}{8}:\frac{1}{12}=12:8=3:2
thus, molecular formula will be C_{2}O_{3}
Answer:
The boiling point of the fluoromethane (CH3F) is higher than that of fluorine (F2).
Since the pressure is constant, you can use the equation V₁/T₁=V₂/T₂ and solve for T₂. (T₂=(T₁/V₁)V₂)
since this is a gas law type question, the temperatures need to be in kelvin therefore you need to convert 15°C to kelvin. 15°C+273=288K. The volume are already in L so they don't have to be converted.
now you just need to plug everything in:
T₂=(288K/99L)x1200L
T₂=3491K
The answer is you need if you have a 99L of gas at 288K, you have to increase the temperature to 3491K to get a volume of 1200L if the pressure remains constant.
I hope this helps. Let me know in the comments if anything is unclear.
The atoms of hydrogen that are present in 7.63 g of ammonia(NH3)
find the moles of NH3 =mass/molar mass
7.63 g/ 17 g/mol = 0.449 moles
since there is 3 atoms of H in NH3 the moles of H = 0.449 x 3 = 1.347 moles
by use of 1 mole = 6.02 x10^23 atoms
what about 1.347 moles
= 1.347 moles/1 moles x 6.02 x10^23 atoms = 8.11 x10^23 atoms of Hydrogen
The answer: The answer is B