Question

How many moles of He are in 16 g of the element?

Answer 1

`4" moles of He"`

Explanation:

Look at the periodic table and find the molar mass of Helium.

This tells us that `4.00` grams of `"Helium"` equates to `1" mole"`. We write it as follows:

`color(white)(aaaaaaaaaaaaaaaaa)(4.00"g He")/(1" mole")`

If we are given `16" grams"` of `"He"`, then we can use what we wrote above to figure out number of `"moles"` of `"He"`.

`(16cancel"g He")/(1) * (1" mole")/(4.00cancel"g He") = 4" moles of He"`

`"Answer": 4" moles of He"`