More Fun with Moles
1. What is the mass, in grams, of each of the following? a)
1.00 mol lithium 6.94 g Li
b) 1.00 mol aluminum 27.0 g Al
c) 6.022x1023 atoms carbon 12.01 g C
d) 6.022x1023 atoms silver107.9 g Ag
2. Determine the mass, in grams of each of the following.
a) 3.00 mol aluminum 80.9 g Al
b) 4.25 mol lithium 29.5 g Li c) 1.38 mol nitrogen 38.7 g
N2 d) 2.57x108 mol sulfur 8.24 x 109 g S
3. How many moles of each substance are represented by
the following?
a) 40.1 g calcium 1.00 mol Ca b) 11.5 g sodium 0.500 mol
Na c) 0.00750 g silver 6.95 x 10-5 mol Ag d) 4.5x10-12 g
oxygen 1.4 x 10-13 mol O2
4. How many moles are equal to
a) 2.25x1025 atoms zinc 37.4 mol Zn b) 50 atoms barium
8 x 10-23 mol Ba c) 6.02x1023 atoms neon 1.00 mol Ne
5. How many atoms are in each of the following:
a) 1.5 mol sodium 9.0 x 1023 Na atoms b) 6.76 mol lead
4.07 x 1024 Pb atoms c) 0.25 mol chlorine 3.0 x 1023 Cl
atoms
6. What is the mass, in grams, of
a) 4.5x1012 atoms chlorine 2.6 x 10-10 g Cl
b) 8.42x1018 atoms bromine 1.12 x 10-3 g Br
7.
a)
b)
c)
How many atoms are in:
5.4 g nitrogen 2.3 x 1023 N atoms
8.02 g sulfur 1.51 x 1023 S atoms
1.5 g potassium 2.3 x 1022 K atoms
8.
a)
b)
c)
d)
Which element in each pair contains the most atoms?
0.5 mol carbon or 0.75 mol lithium
19 g fluorine or 20 g neon same
0.25 mol silicon or 10 g chlorine
15.0 g calcium or 40.0 g silver
9. Name these ionic compounds:
a) TiSO3 titanium (II) sulfite b) Bi3(PO4)2 bismuth (II)
phosphate c) Fe(MnO4)2 iron (II) permanganate d) HgS
mercury (II) sulfide e) SnO2 tin(IV) oxide f)
PbCO3 lead (II) carbonate
10. How many grams of each element has the same number
of atoms as 12 g aluminum? a) oxygen 7.1 g O b)
chlorine 16 g Cl c) calcium 18 g Ca d) nickel 26 g Ni
e) lead 92 g Pb
11. If 4.75x1023 atoms of silver are placed
on a balance. How many atoms of gold
would have the same mass? 2.60 x 1023 atoms Au
12. A garnet has the chemical formula Fe3Al2(SiO4)3.
How many moles of each element are present in five
moles of garnet? 15 mol Fe, 10 mole Al, 15 mole Si and
60 mole O
13. Find the percent metal in each compound:
a) sodium chloride 39.34% Na b) cobalt (II) chlorate
26.09% Co c) barium acetate 53.764% Ba
14. A 25.0 g sample of an orange compound contains
6.64 g potassium, 8.84 g chromium and 9.52 g oxygen.
Find the empirical formula.
K2Cr2O7
15. When 5.0 g of ethanol is burned, 2.61 g of carbon,
0.657 g hydrogen and 1.73 g oxygen are released. What
is the empirical formula for ethanol? C2H6O If ethanol’s
molar mass is 46 g, what is the molecular formula?
C2H6O
16. Vitamin C contains 40.91% carbon, 4.59%
hydrogen and 54.50% oxygen. If vitamin C’s molar
mass is 180 g/mol, what is the molecular formula?
C6H8O6
17. Name these covalent compounds:
a) OF2 oxygen difluoride b) PF3 phosphorus trifluoride
c) XeF4 xenon tetrafluoride d) N2O dinitrogen
monoxide e) N2F2 dinitrogen difluoride
18. Write formulas for these ionic compounds:
a) tin (IV) carbonate Sn(CO3)2 b) lead (II) chlorate
Pb(ClO3)2 c) aluminum peroxide Al2(O2)3 d) cesium
hydrogen sulfate CsHSO4
19. Determine the empirical formula of the comound
that is 43.2% by mass K, 39.1% Cl and also contains
oxygen. Name this ionic compound.
KClO – potassium hypochlorite
20. Determine the empirical formula for a compound if
an 83.45 g sample contains 22.03 g sodium, 30.71 g
sulfur and the rest oxygen. If the molar mass of this
compound is 174.12, what is the molecular formula?
Na2S2O4