Answer:
45.45 ml of dimethyl sulfoxide
Explanation:
density of dimethyl sulfoxide is 1.10 g/10⁻³L which is 1.10 g/mL
now we devise the next reasoning:
If 1.10 g of dimethyl sulfoxide have a volume of 1 mL
Then 50 g of dimethyl sulfoxide have a volume of X mL
X = (50 × 1) / 1.10 = 45.45 ml of dimethyl sulfoxide
Answer: 0.0826mol
PV=nRT
n=PV/RT
n=(1atm)(2.1L)/(310K)(0.082057L*atm/mol*K)=0.0826mol
Answer:- 10 L of ethane.
Solution:- The given balanced equation is:

From this equation, ethane and oxygen react in 2:7 mol ratio, the ratio of volumes would also be same if they are at same temperature and pressure.
Since 14 L of each gas are taken, the oxygen will be the limiting reactant and ethane will be the excess reactant. Let's calculate the volume of ethane used:

= 
From above calculations, 4 L of ethane are used. So, excess volume of ethane left after the completion of reaction = 14 L - 4 L = 10 L
Hence, 10 L of ethane will be remaining.
Argon is a suitable choice for light bulbs because it is inert. Compared to a reactive gas like oxygen, the metal filimant would burn up in a reactive environment, which is why a noble gas is used.