Section: 6.1
20) calculate the number of moles of aspirin, c9h8o4, in a 4.0 gram tablet.
a) 2.2 x 10-4 ċ 9 h: 8 0.4
b) 2.2
c 12.61 h 1.01 16.00
c) 4.6 x 10-3
9x612.01) + 8x (1.01) +4 (16.00) - 180.17
d) 0.022
4.0 x (180.17)=720

D = 0.022 moles

Explanation:

Given data:

Mass of aspirin = 4.0 g

Number of moles = ?

Solution:

First of all we will calculate the molar mass of aspirin.

Molar mass of aspirin= 12×9 + 1×8 + 16× 4

Molar mass of aspirin= 108 + 8 + 64

Molar mass of aspirin=  180 g/mol

Number of moles = mass/molar mass

Number of moles = 4.0 g/ 180 g/mol

Number of moles =  0.022 mole