Question

Calculate the percentage of each element in acetic acid, hc2h3o2, and glucose, c6h12o6.

b. these two substances have the same empirical formula. what would you expect the percentage composition of the empirical formula to b

Answer 1

Acetic acid, HC2H3O2

First, calculate for the molar mass of acetic acid as shown below.
M = 1 + 2(12) + 3(1) + 2(16) = 60 g

Then, calculating for the percentages of each element.
Hydrogen:
P1 = ((4)(1)/60)(100%) = 6.67%

Carbon:
P2 = ((2)(12)/60)(100%) = 40%

Oxygen
P3 =((2)(16) / 60)(100%) = 53.33%

Glucose, C6H12O6

The molar mass of glucose is as calculated below,
6(12) + 12(1) + 6(16) = 180

The percentages of the elements are as follow,
Hydrogen:
P1 = (12/180)(100%) = 6.67%

Carbon:
P2 = ((6)(12) / 180)(100%) = 40%

Oxygen:
P3 = ((6)(16) / 180)(100%) = 53.33%

b. Since the empirical formula of the given substances are just the same and can be written as CH2O then, the percentages of each element composing them will just be equal.