Question

What is the mass of 7.2 moles of titanium to the nearest tenth?

Answer 1

7.2 moles of titanium weigh 344.7 grams.

Step-by-step explanation:

Molar mass of titanium = 47.88 g

`1 \: mole \: of \: titanium = 47.88 \: grams \\ 7.2 \: moles \: of \: titanium = g`

solve for g

`g = ( (7.2 * 47.88)/(1) ) \\ g = 344.7 \: grams`

Answer 2

`\boxed {\boxed {\sf 344.7 \ g \ Ti}}`

Step-by-step explanation:

We are asked to find the mass of 7.2 moles of titanium.

To convert from moles to grams, we use the molar mass. This value is the mass of 1 mole of a substance. They are equivalent to the atomic masses found on the Periodic Table, but the units are grams per moles instead of atomic mass units.

Look up titanium's molar mass on the Periodic Table.

• Ti: 47.87 g/mol

Convert moles to grams using dimensional analysis. First, set up a ratio using the molar mass.

`\frac {47.87 \ g \ Ti}{1 \ mol \ Ti}`

We are converting 7.2 moles to grams, so we multiply the ratio by this value.

`7.2 \ mol \ Ti *\frac {47.87 \ g \ Ti}{1 \ mol \ Ti}`

The units of moles of titanium cancel.

`7.2 *\frac {47.87 \ g \ Ti}{1 }`

The denominator of 1 can be ignored (a number over 1 is just the number).

`7.2 *47.87 \ g \ Ti}`

`344.664 \ g \ Ti`

We are asked to round to the nearest tenth. The 6 in the hundredth place tells us to round the 6 in the tenth place up to a 7.

`344.7 \ g \ Ti`

There are approximately 344.7 grams of titanium in 7.2 moles of titanium.