Answer:
The number of molecules = 2.6408 molecules
Explanation:
To determine the number of molecules in water, we need to determine how many moles of water we have
Water has a molar mass of 18.015g/mol, this means that one mole of water molecules has a mass of 18.015g
To find the number of molecules,
7.9g * 1 mole H2O/ 18.015g
= 0.4385mole of H2O
Using avogadro number,
0.4385 H2O * 6.022* 10^23molecules/ 1 mole of H2O
That's 0.4385 H2O multipled by 6.022*10^ 23 molecules divided by 1 mole of H2O
Which gives == 2.6408 molecules
