Question

Find the mass of 3 moles of ethanol C2H5OH. ]C=12,H=1,O=16]​

Answer 1

Answer:

Molar mass of C²H5OH = 12*2+1*5+16+1

= 24+5+16 +1 =46 g

as we know 1 mole = molar mass in grams

therefore 3 mole = 3*molar mass

= 3*46

= 138

Answer 2

Given:

Moles of ethanol = 3 moles

mass of carbon = 12

mass of hydrogen = 1

mass of oxygen = 16

To find:

Mass of 3 moles of ethanol=?

Solution:

Mass of 3 moles of ethanol can be found in the following way:

=> We know that 1 mole of any substance contains mass equal to the constituents of the chemical compound.

=> The formula of ethanol = C₂H₅OH

=> Mass of 1 mole of ethanol = 2(mass of carbon) + 6 (mass of hydrogen) + 1 (oxygen)

=> Mass of 1 mole of ethanol = 2(12) + 6(1) + 1(16)

=> Mass of 1 mole of ethanol = 24 + 6 + 16

=> Mass of 1 mole of ethanol = 46 grams

∴ Mass of 3 moles of ethanol = 3(46 grams)

=> Mass of 3 moles of ethanol = 138 grams

Hence, the mass of 3 moles of ethanol is 138 grams.