Answer : The pressure of the helium gas is, 1269.2 mmHg
Explanation :
To calculate the pressure of the gas we are using ideal gas equation:

where,
P = Pressure of
gas = ?
V = Volume of
gas = 210. mL = 0.210 L (1 L = 1000 mL)
n = number of moles
= 0.0130 mole
R = Gas constant = 
T = Temperature of
gas = 
Putting values in above equation, we get:


Conversion used : (1 atm = 760 mmHg)
Thus, the pressure of the helium gas is, 1269.2 mmHg
1/6 x 1/6 x 1/6= solve the rest
molar mass of methane CH4
= C + 4 H
= 12.0 + 4 x 1.008
= 12.0 + 4.032
= 16.042g/mol
7.31 x 10^25 molecules x <u> 1 mole CH4 </u> = 121.43 moles
6.02 x 10^23 CH4 molecules
121.43 moles CH4 are present.
Answer:
Oxygen and sulfur
Explanation:
Alloys consist of metals fused together sometimes with additional components, such as carbon, to prevent metals from corrosion.
Oxygen and sulfur are two compounds consisting of non-metal atoms, O and S. Combining oxygen with sulfur would actually produce sulfur dioxide, a gas, in contrast to a metallic substance that is fused with some other metal or carbon.
That's the reason why combination of sulfur and oxygen wouldn't produce an alloy: it would produce a gas.