How many moles of oxygen atoms are in one mole of Ca3(PO4)2?
8 moles
Given the balanced equation representing a reaction:
NH3(g) + O2(g) →N2(g) + H2O(g) + energy
What mass of ammonia completely reacts with 15g of oxygen to produce 32 g of nitrogen and 40g of water?
57g
The coefficients in a balanced chemical equation represent
(l ) the mass ratios of the substances in the reaction
(2) the mole ratios of the substances in the reaction
(3) the total number of electrons in the reaction
(4) the total number of elements in the reaction
(2) the mole ratios of the substances in the reaction
Given the balanced equations representing two chemical reactions:
2 NaBr → 2 Na + Br2
AgNO3 + NaCl → NaNO3 + AgCl
Which types of chemical reactions are represented by these equations?
(1) single replacement and decomposition
(2) single replacement and double replacement
(3) synthesis and decomposition
(4) decomposition and double replacement
(4) decomposition and double replacement
The gram-formula mass of a compound is 36 grams. The mass of one mole of this compound is
1) 22.4 L
2) 6.02x1023 molecules
3) 36.0g
4) 1 mole
3) 36.0g
What is the total number of moles of atoms in 1 mole of Fe2(SO4)3
17 moles of atoms
Finish balancing the following equation using the smallest whole-number coefficients:
2Sb2S3(s) + O2(g) → Sb2O3(s) + SO2(g)
2Sb2S3(s) + 9O2(g) → 2Sb2O3(s) + 6SO2(g)
The balanced equation below represents the reaction between carbon monoxide and oxygen to produce carbon dioxide.

Determine the number of moles of O2(g) needed to completely react with 8.0 moles of CO(g).
4 moles
Given the balanced equation representing a reaction:
2H2 + O2 → 2H2O + energy
Which type of reaction is represented by this equation?
Synthesis
How many molecules are contained in 0.50 moles of H2 at STP?
3.0x1023 molecules
How many moles of C6H12O6 would you need to have 18 moles of carbon?
3 moles of C6H12O6
What is the missing product in the following equation? Pb(NO3)2 + 2NaI --> PbI2 + 2______
1) Na2O
2) Na2NO3
3) NaNO3
4) Na2(NO3)2
3) NaNO3
What is the mole-to-mole ratio between Al and Al2O3 in the following balanced equation?
8 Al + 3 Fe3O4 ---> 4 Al2O3 + 9 Fe ?
2:1
What is the name of the group that contains nonmetals that are most likely to undergo a chemical reaction?
Halogens
How many liters of space would 2.5 moles of helium occupy at STP?
56 L
What is the percent by mass of oxygen in NaOH?
40%
Explain why the balanced equation below represents a conservation of atoms.
6Li + N2 → 2Li3N
Same # of atoms of each element on both sides of the equation
Given the equation: CH4 + 2O2 --> CO2 + 2H2O
How many moles of oxygen are needed for the complete combustion of 3.0 moles of methane?
6 moles
The equation below is best classified as which type of chemical reaction?
2C2H2 + 7O2 --> 4CO2 + 6H2O
Combustion
Determine the number of moles of vitamin C [C6H8O6] in an orange that contains 0.071 grams of C6H8O6.
4.03x10-4 or 0.000403 moles
What is the percent composition by mass of hydrogen in NH4OH?
14.3%
Given the unbalanced equation: Ca(OH)2 + (NH4)2SO4 ---> CaSO4 + NH3 +H2O.
What is the sum of the coefficients when the equation is completely balanced using the smallest whole-number coefficients?
7
Given the reaction: 2C2H2(g) + 5O2(g) --> 4CO2(g) + 2H2O(g), what is the total number of grams of O2(g) needed to react completely with 13 grams of C2H2(g)?
40 grams of O2(g)
For the following reaction, identify the type and state why.
2NaHCO3 + heat --> Na2CO3 + H2O + CO2
Decomposition because one reactant is breaking down into several products
How many grams of Ar(g) at STP would occupy 67.2L?
120 grams