Answer:
[tex]31.8\ moles = 1.91 * 10^{25}\ molecules[/tex]
Explanation:
Given
31.8 moles of water
Required
Determine the number of molecule
In standard units: 1 molecule of water is:
[tex]1\ mole = 6.022 * 10^{23}\ molecules[/tex]
Multiply both sides by 31.8
[tex]31.8 * 1\ mole = 31.8 * 6.022 * 10^{23}\ molecules[/tex]
[tex]31.8\ moles = 31.8 * 6.022 * 10^{23}\ molecules[/tex]
[tex]31.8\ moles = 191.4996 * 10^{23}\ molecules[/tex]
Express 191.4996 as a standard form
[tex]31.8\ moles = 1.914996 * 10^2 * 10^{23}\ molecules[/tex]
Apply law of indices:
[tex]31.8\ moles = 1.914996 * 10^{2+23}\ molecules[/tex]
[tex]31.8\ moles = 1.914996 * 10^{25}\ molecules[/tex]
Approximate:
[tex]31.8\ moles = 1.91 * 10^{25}\ molecules[/tex]
