What is the mass in grams of 9.77*10^24 molecules of methanol (CH3OH) ?

mass of methanol = 519.3 g

Explanation:

Given dа ta:

molecules of CH3OH = 9.77 * 10∧ 24

mass in gram = ?

Solution:

First of all we will calculate the number of moles:

(9.77 * 10∧ 24) * 1 mol / 6.02 * 10∧23 = 16.229 moles

Now we will calculate the mass in gram:

Formula:

number of moles = mass / molar mass

16.229 mole = mass / 32 g/mol

mass = 16.229 mol * 32 g / mol

mass = 519.3 g

Simple method:

molar mass of CH3OH is 32 g so according to Avogadro number,

32 g of CH3OH = 6.02 * 10∧23 molecules

9.77*10^24 molecules will be equal to

(32 g of CH3OH / 6.02 * 10∧23 molecules) * 9.77*10^24 molecules

= 5.136 * 10∧-23 g/molecules * 9.77*10^24 molecules

= 519.3 g