Question

Determine the molecular formula for glucose, with a molar mass of 180 grams, if the empirical formula for glucose is CH2O.

CH2O

C2H4O2

C3H6O3

C6H12O6

Answer 1

take the empirical formula CH2O

adding the atomic masses
12 + 2*1 + 16 = 30

Now divide 180 by 30

Answer 2

what do you get?

Answer 3

that gives you the factor you'll use to find the molecular formula

Answer 4

180 / 30 = ?

Answer 5

Let me see..
P.S. sorry I was gn for a moment.

Answer 6

Molecular formula=\((empirical formula)_n\)

Answer 7

C = 12 / MM CH2O (30) = 40 % H = 2/30 = 6.67% ; O = 16 / 30 = 53.33 %


C = 40% of 180g = 76g or 6 moles of C
H = 6.67 % of 180 = 12g or 12 moles of H
O = 53.93% of 180 = 98 g or 6 moles of O

Answer 8

n=(molar mass)/(empirical mass)

Answer 9

Empirical mass=12*1+1*2+1*16=30
Molar mass=180
n=6

Answer 10

Molecular formula=\((CH_2O)_n\)

Answer 11

Molecular formula=\((CH_2O)_6\)

Answer 12

yes n = 180/30 = 6

Answer 13

You need to find its mole ratio
mol = mass/ Mr
180/(12+2+16)=180/30 = 6

Now you need to multiply it with the empiric formula :)

Answer 14

So @welshfella, the answer is C6H12O6.

Answer 15

In this case there is no need to work out the percentages of each of the elements

Answer 16

yes

Answer 17

YEAH!!!! I DID IT!
Thanks guys!

Answer 18

yw

Answer 19

urwel