Question

it was determined through analysis that a compound, sodium carbonate with a molar mass of 263 g/mol contained 68.4% water. determine the toilet number of water molecules in this hydrate

Answer 1

Answer:

$molec_{water}=6.016*10^{24}molecules$

Explanation:

Hi, here I explain step by step:

1) You have 263 g/mol and 68.4% of that (in weight) is water. So for 1 mol:

$m_{water}=0.684*263 g$

$m_{water}=179.89 g$

2) A mol of water molecules weights 18 g/mol (16 g/mol of oxygen and 2g/mol of hydrogen):

$n_{water}=\frac{179.89g}{18g/mol}$

$n_{water}=9.99 mol$

3) Knowing Avogadro's number: 6.022*10^23 molec/mol:

$molec_{water}=9.99 mol*6.022*10^{23}molec/mol$

$molec_{water}=6.016*10^2^4molec$