Question

How many grams of sodium chloride are needed to make 17.5g of sodium?

Answer 1

Answer : The mass of
`NaCl` needed are, 44.5 grams.

Explanation :

First we have to calculate the moles of Na.

`\text{Moles of }Na=\frac{\text{Given mass }Na}{\text{Molar mass }Na}=(17.5g)/(23g/mol)=0.761mol`

Now we have to calculate the moles of NaCl.

The balanced chemical reaction is:

`2NaCl\rightarrow 2Na+Cl_2`

From the reaction, we conclude that

As, 2 mole of
`Na` produces from 2 mole of
`NaCl`

So, 0.761 mole of
`Na` produces from 0.761 mole of
`NaCl`

Now we have to calculate the mass of
`NaCl`

`\text{ Mass of }NaCl=\text{ Moles of }NaCl* \text{ Molar mass of }NaCl`

Molar mass of
`NaCl` = 58.5 g/mole

`\text{ Mass of }NaCl=(0.761moles)* (58.5g/mole)=44.5g`

Therefore, the mass of
`NaCl` needed are, 44.5 grams.