A compound contains of carbon hydrogen and nitrogen contains 66.70/ carbon 7.41/ hydrogen and 25.90/ nitrogen .The molecular mass of compound was found to be 108 .Find the emprical formula of the compound.
Answers
Answer:
Explanation:
Find the percentage of Oxygen by adding all of the given percentages then subtracting from 100
20.0
+
6.66
+
47.33
=
73
.
999
=
74
100
−
74
=
26
Change the percentages to grams. If there were 100 grams
C= 20 grams H = 6.66 grams N = 47.33 grams O = 26 grams.
Change the grams to moles by dividing by the molecular mass of the elements
Moles Carbon =
20
12
=
1.66
moles C
Moles Hydrogen =
6.66
1
=
6
66
moles H
Moles Nitrogen =
47.33
14
=
3.38
moles N
Moles Oxygen =
26
16
=
1.625
moles O
Find the simplest mole ratios.
Since Oxygen is the smallest divide all the other nu=mber of moles by the moles of Oxygen
Carbon ratio =
C
O
=
1.66
1.625
=
1.02
or 1:1
Nitrogen ratio =
N
O
=
3.38
1.625
=
2.04
or 2:1
Hydrogen ratio =
H
O
=
6.66
1.625
=
4.09
or 4:1
So the compound has a ratio of 1 C: 2 N : 4 H : 1O for the empirical formula
The mass of one empirical formula is 62 grams per mole. This is slightly higher than the experimental molecular mass of 60 grams but is within experimental error.
So the compound most likely has a formula of
C
N
2
H
4
O
The Compound would look something like this
H
I
H-N-C = O
I
N-H
I
H
The valance bonding of each atom is complete
C = 4 bonds
N = 3 bonds
O = 2 bonds
H = 1 bond