Question

What’s the mass of 1.5 moles of c6h14

Answer 1

12*6 = 72
1*14 = 14
1.5 * (72+14)
Answer = 129

Answer 2

`\boxed {\boxed {\sf 129.267 \ g \ C_6H_(14)}}`

Step-by-step explanation:

To convert from moles to mass, the molar mass is used. This is the grams per mole for a substance.

The values are found on the Periodic Table. They are the same as the atomic masses, but the units are grams per mole instead.

We are given this compound: C₆H₁₄. Look up the molar masses for the individual elements first: carbon and hydrogen.

• C: 12.011 g/mol
• H: 1.008 g/mol

Check the subscripts, which tell us the number of atoms per molecule. There are 6 carbon atoms and 14 hydrogen atoms. Multiply the molar mass by that number, then add them together.

• C₆: 12.011*6=72.066 g/mol
• H₁₄: 1.008*14=14.112 g/mol

• C₆H₁₄: 72.066+14.112=86.178 g/mol

Use the molar mass as a ratio.

`\frac {86.178 \ g \ C_6H_(14)}{1 \ mol \ C_6H_(14)}}`

Multiply by 1.5 moles.

`1.5 \ mol \ C_6H_(14) * \frac {86.178 \ g \ C_6H_(14)}{1 \ mol \ C_6H_(14)}}`

The moles of C₆H₁₄ will cancel each other out.

`1.5 * \frac {86.178 \ g \ C_6H_(14)}{1}}`

`1.5 * {86.178 \ g \ C_6H_(14)}`

`129.267 \ g \ C_6H_(14)`

1.5 moles of C₆H₁₄ is equal to 129.267 grams of C₆H₁₄