Question

Determine which of the following contains greatest mass of hydrogen: 1 mol of CH4, 0.6 mol of C6H6, or 0.4 Mol of
C3H8.

Answer 1

Answer:

1 mol of CH₄  will contain greatest mass of the oxygen i.e 4 grams

Explanation:

Given;

1 mol of CH₄

0.6 mol of C₆H₆

0.4 Mol of  C₃H₈.

Now,

moles = Mass / Molar mass

Thus,

for 1 mol of CH₄

1 = mass /  ( 12 + 4 × (1) )

or

mass = 16 grams

now,

16 grams of CH₄ contains 4 grams of hydrogen

and, for 0.6 mol of C₆H₆

0.6 = Mass / ( 12 × 6 + 6 × 1)

or

Mass = 46.8 grams

Now,

78 grams of CH₄ contains 6 grams of hydrogen

thus,

46.8 grams of CH₄ will contain = (6 / 78) × 46.8 grams of hydrogen

or

46.8 grams of CH₄ will contain = 3.6 grams of hydrogen

and, for 0.4 Mol of  C₃H₈

0.4 = mass / (3 × 12 + 8 × 1)

or

Mass of 0.4 Mol of  C₃H₈ = 17.6 grams

Now,

44 grams of  C₃H₈ contains 8 grams of hydrogen

thus,

17.6 grams of  C₃H₈ will contain = ( 8 / 44 ) × 17.6 grams of hydrogen

or

17.6 grams of  C₃H₈ will contain = 3.2 grams of hydrogen

Hence,

1 mol of CH₄  will contain greatest mass of the oxygen i.e 4 grams

Answer 2

Answer: 1 mole of methane has the greatest mass of hydrogen.

Explanation:

To calculate the mass of hydrogen, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$      .....(1)

• For 1 mole of $CH_4$

In 1 mole of methane, 1 mole of carbon atom and 4 moles of hydrogen atoms are there.

Molar mass of hydrogen = 1 g/mol

Moles of hydrogen = 4 moles

Putting values in equation 1, we get:

$4mol=\frac{\text{Mass of hydrogen}}{1g/mol}\\\\\text{Mass of hydrogen}=4g$

The mass of hydrogen in 1 mole of $CH_4$ is 4 g

• For 0.6 mole of $C_6H_6$

In 1 mole of benzene, 6 moles of carbon atoms and 6 moles of hydrogen atoms are there.

So, in 0.6 moles of benzene, (6 × 0.6) = 3.6 moles of carbon atoms and (6 × 0.6) = 3.6 moles of hydrogen atoms are there.

Molar mass of hydrogen = 1 g/mol

Moles of hydrogen = 3.6 moles

Putting values in equation 1, we get:

$3.6mol=\frac{\text{Mass of hydrogen}}{1g/mol}\\\\\text{Mass of hydrogen}=3.6g$

The mass of hydrogen in 0.6 mole of $C_6H_6$ is 3.6 g

• For 0.4 mole of $C_3H_8$

In 1 mole of $C_3H_8$, 3 moles of carbon atom and 8 moles of hydrogen atoms are there.

So, in 0.4 moles of $C_3H_8$, (3 × 0.4) = 1.2 moles of carbon atoms and (8 × 0.4) = 3.2 moles of hydrogen atoms are there.

Molar mass of hydrogen = 1 g/mol

Moles of hydrogen = 3.2 moles

Putting values in equation 1, we get:

$3.2mol=\frac{\text{Mass of hydrogen}}{1g/mol}\\\\\text{Mass of hydrogen}=3.2g$

The mass of hydrogen in 0.4 mole of $C_3H_8$ is 3.2 g

Hence, 1 mole of methane has the greatest mass of hydrogen.