NAME: ADORZA SHANDELLE
SECTION: BS PSY 3108
,
F
Chemistry: Molar Mass, Mole and Percentage
Composition
Calculate the molar masses and percentage composition of each of the following compounds. Show
your work and always include units.
%
o
1. Ca3P2
Ca
P
40
=
.
I
089 90p=40974mo1x10
30-97g(m)
=
Composition
Toca
2. Ca(OH) 2
=08/mox100
molCape
182
.
%Composition
=
46.
o
189/mo)
:
m x0
400 in%H
a
↳
IEttoca
Ga
2.
:
4/mol
74 19/mol
.
=
3. Na2SO4
Nanso
43 18 % 8
It
.
It390
% composition
x=yo
I
a
I
o
-
4. CaSO4
%o composition
=37
.
9019
079/mol
=
10084/mol)
136
5. (NH4) 2SO4
i
6. Zn3(PO4) 2
tu
·
7. Mg(NO3) 2
=14 01 % mol
.
8. KCl
FiI To
9. Prozac
66
.
00 90 C
% 2
=
.
159/mol
6009/mol) x100
%00:
x 100
:
29
.
4490 Ca
136
=
.
159/mol
47 01 % 0
.
umx=22559 at
10.Who is your crush :D (classmate only)
1. Acetic acid is more commonly known as vinegar and has the formula CH3COOH.
a. What is the molar mass of CH3COOH?
b. How many moles are in 5.6 grams of acetic acid?
2. How many grams are in 0.890 moles of copper (I) bromide?
3. Calculate the molar mass of calcium bromide.
4. How many moles of lithium atoms are in 3.75 x 1012 lithium atoms?
5. What is the mass of 6.80 x 1024 molecules of C6H12O6?
6. A sample of exactly 5 moles of H2O was found to contain 90.05 grams. What is
the molar mass of H2O?
7. How many moles are in 45.8 mg of Sr3(PO4)2?
8. How many moles are in 548 mg of H2O?
9. Which has a greater mass: copper (I) sulfate or copper (II) sulfate?
10. How many moles of hydrogen are in a 10 g sample of CH3CHO?
11. How many moles of phosphate ions are in 30.5 g of iron (II) phosphate?
12. How many grams of hydrogen are in a 25 g sample of C12H22O11?
13. Sinong crush ng crush mo? XD
A.
Determine the empirical formula of each compound from its percentage composition by
weight:
1) 66.4% Cu, 33.6% S
3) 39.8% K, 27.8% Mn, 32.5% O
2) 79.8% Cu, 20.2% S
4) 32.4% Na, 22.6% S, 45.0% O
B. Determine the empirical formula of each compound from the given weights:
1) 7.615 g Ga, 2.622 g O
3) 11.89 g Fe, 5.11 g O
2) 0.366 g Na, 0.220 g N, 0.752 g O
4) 87.3 g Na, 121.5 g S, 91.2 g O
C. Determine the molecular formula of each compound from the empirical formula and the
molecular weight:
1) E.F. = NaS2O3, mol. wt. = 270.4
4) E.F. = Na2SiO3, mol. wt. = 732.6
2) E.F. = C3H2Cℓ, mol. wt. = 147.0
5) E.F. = NaPO3, mol. wt. = 305.9