Question

How many grams of sodium is equal to 6.92 x 10 21atoms of sodium?

Answer 1

`Amount\ of\ Grams = 0.2644 g`

Step-by-step explanation:

Given

Element: Sodium

`Atoms = 6.92 * 10^(21)`

Required

Determine the amount of grams

We start by solving for the number of moles

`Moles = (Sodium\ Atoms)/(Avogadro\ Number)`

`Avogadro\ Number = 6.022 * 10^(23)`

So, we have:

`Moles = (6.92 * 10^(21))/(6.022 * 10^(23))`

`Moles = (6.92 * 10^(21-23))/(6.022)`

`Moles = (6.92 * 10^(-2))/(6.022)`

`Moles = 1.15 * 10^(-2)` moles

Next, we calculate the amount of grams.

Mass per mol of Sodium = 22.98977g/mol

For
`1.15 * 10^(-2)` moles of sodium

`Amount\ of\ Grams = 1.15 * 10^(-2)\ mol * 22.98977g/mol`

`Amount\ of\ Grams = 1.15 * 10^(-2) * 22.98977g`

`Amount\ of\ Grams = 0.264382355 g`

`Amount\ of\ Grams = 0.2644 g` (approximated)

Hence, there are 0.2644g of sodium in
`6.92 * 10^(21)` atoms