Answer:
Option D. CO2.
Step-by-step explanation:
Data obtained from the question include:
Mass = 0.301 g
Volume = 0.153 L
Next, we shall determine the density of the gas. This is shown below:
Density = mass /volume
Density = 0.301/0.153
Density = 1.967 g/L
At standard temperature and pressure, the volume occupied by 1 mole of a gas is 22.4L.
Note: When we divide the molar mass of any gas by its density at STP, the volume obtained is 22.4L.
Now let us determine the identity of the gas.
For CH4:
Molar mass of CH4 = 12 + 4 = 16 g/mol
Density = 1.967 g/L
Volume =?
Volume = molar mass / Density
Volume = 16/1.967
Volume = 8.13 L
For NH3:
Molar mass of NH3 = 14 + (3x1) = 17 g/mol
Density = 1.967 g/L
Volume =?
Volume = molar mass / Density
Volume = 17/1.967
Volume = 8.64 L
For C2H6:
Molar mass of C2H6 = (12x2) + (6x1) = 30 g/mol
Density = 1.967 g/L
Volume =?
Volume = molar mass / Density
Volume = 30/1.967
Volume = 15.25 L
For CO2:
Molar mass of CO2 = 12 + (2x16) = 44 g/mol
Density = 1.967 g/L
Volume =?
Volume = molar mass / Density
Volume = 44/1.967
Volume = 22.4 L
From the above illustration, only CO2 gave a value of 22.4 L which is the standard value for the volume of a gas at stp.
Therefore, the gas is CO2.