Question

In nuclear fusion, about 0.60% of the mass of the fusing substance is converted to energy. What mass in grams is converted into energy when 22 kg of substance undergoes fusion?

Answer 1

First convert kilograms to grams, then convert the percent-mass into mass.

Explanation:

There are 1000 grams in a kilogram, so the first step is to multiply the mass in kilograms by 1000 to find the mass in grams.

`22kg*1000 = 22,000 g`

From here, we can go one of two ways, with each arriving at the same conclusion:

Multiply the total mass in grams by the percent of the mass that is converted into energy and then divide it by `100%` to find the mass converted into energy in grams

`22,000g * (0.60%)/(100%) = 132 g` is converted into energy

or

Divide the total mass in grams by 100%, to find the value of 1%, which you can then multiply by the percent-mass converted into energy 0.6% to find the mass that is converted into energy in grams

`(22,000g)/(100%) * 0.60% = 132 g` is converted into energy