CHEMISTRY D425 EXAM WITH ACTUAL QUESTIONS
AND 100% VERIFIED ANSWERS | LATEST 2025/ 2026
UPDATE | GRADED A+ | 100% SUCCESS
which would be investigated in reaction stoichiometry - correct answer -
the mass of potassium required to produce an unknown mass of
potassium chloride
given the balance equation, how many moles of water H2O are
produced by the complete reaction of 4.0 moles C2H6?
2CH6+ 7O2-> 6H2O+ 4CO2 - correct answer -
given the balanced equation how many grams of water
(H2O=18.015g/mol) are produced by the complete reaction of 5.22
moles O2
2C2H6+ 7O2-> 6H2O + 4CO2 - correct answer -
given the balanced equation how many grams of hydrogen gas
(H2= 2.016 g/mol) are produced by the complete reaction of 489.2 g of
hydrochloric acid (HCL= 36.458 g/mol)
,2Na (s) + 2HCl (aq) -> 2NaCl (aq) + H2 (g) - correct answer -
given the balanced equation how many moles of hydrogen gas (H2) are
produced by the complete reaction of 2.11 x 10^22 atoms of Na
2Na (s) + 2HCl (aq) -> 2NaCl (aq) + H2 (g) - correct answer -
what happens to a reaction when a limiting reactant in a chemical
reaction is completely used up - correct answer -the reaction stops
how many moles of potassium chloride are required to yield 250g of
oxygen in the reaction
2KClO3 -> 2KCl+ 3O2 - correct answer -5.2 mol
convert 250.0 grams to moles:
moles=mass/ molar mass, moles = 250.0/32= 7.81 mol
molar ratio btwn KClO3 and O2 is 2:3
the 2=x moles of KClO3 the 3 = 7.81 mol of O2
15.62=3x 15.62/3= x
cross multiplying to get 5.21 moles =# of moles of KClO3 req.
,if 14.67g of C2H6 is allowed to react with 39.51g of O2 as shown what
would be the limiting reactant
molar mass (g/mole)
C2H6= 30.08, O2= 31.998, H2O= 18.015, CO2= 44.08
2C2H6 + 7O2 -> 6H2O + 4CO2 - correct answer -O2. in order to consume
all the C2H6 we would need 54.62g of O2, we only have 39.51g
what is the maximum amount of product that can be made in a
chemical reaction - correct answer -theoretical yield is calculated by
assuming that all the limited reagent is converted to product
when 10g of copper and 10g of iodine are mixed, 5g of Cul are made.
What is the percent yield of Cul? the theoretical yield is 15g
2Cu+ I2 -> 2Cul - correct answer -33%
percent yield= actual yield/ theoretical yield x 100. If 5g are produced,
then the percent yield is (5g/ 15g) x 100= 33%
describe the study of mass relationships btwn reactants and products in
a chemical reaction - correct answer -quantitative relation btwn the
, number of moles and mass of various products and reactants in a
chemical reaction
calculate the limiting reactant in the chemical equation , knowing that
3.25g of NH3 reacts with 3.50g of O2
4NH3 (g) + 5O2 (g) -> 4NO (g) + 6H2O (l) - correct answer -O2.
4 NH3+5O2 -> 4 NO+6H2O
3.25g of NH3= 3.25g/ 17g mol-1 = 0.19 mol of NH3.
available mass of O2 is 3.50 or
3.50g/32 mol-1 =0.11 mol of O2.
Since (0.11 mol) is less than NH3 (0.19 mol) , the limiting reagent is O2
what is the theoretical yield - correct answer -maximum amount of
product that can be formed in a chemical reaction. Formed based on
the amount of limiting reactant in a chemical reaction
45.599g of phosphorous (P4) were allowed to react w/ 67.900g of
oxygen (O2). If 95.201g of P4O10 were actually produced in the lab
what is the percent yield (%yield=actual yield/theoretical yield x 100)
AND 100% VERIFIED ANSWERS | LATEST 2025/ 2026
UPDATE | GRADED A+ | 100% SUCCESS
which would be investigated in reaction stoichiometry - correct answer -
the mass of potassium required to produce an unknown mass of
potassium chloride
given the balance equation, how many moles of water H2O are
produced by the complete reaction of 4.0 moles C2H6?
2CH6+ 7O2-> 6H2O+ 4CO2 - correct answer -
given the balanced equation how many grams of water
(H2O=18.015g/mol) are produced by the complete reaction of 5.22
moles O2
2C2H6+ 7O2-> 6H2O + 4CO2 - correct answer -
given the balanced equation how many grams of hydrogen gas
(H2= 2.016 g/mol) are produced by the complete reaction of 489.2 g of
hydrochloric acid (HCL= 36.458 g/mol)
,2Na (s) + 2HCl (aq) -> 2NaCl (aq) + H2 (g) - correct answer -
given the balanced equation how many moles of hydrogen gas (H2) are
produced by the complete reaction of 2.11 x 10^22 atoms of Na
2Na (s) + 2HCl (aq) -> 2NaCl (aq) + H2 (g) - correct answer -
what happens to a reaction when a limiting reactant in a chemical
reaction is completely used up - correct answer -the reaction stops
how many moles of potassium chloride are required to yield 250g of
oxygen in the reaction
2KClO3 -> 2KCl+ 3O2 - correct answer -5.2 mol
convert 250.0 grams to moles:
moles=mass/ molar mass, moles = 250.0/32= 7.81 mol
molar ratio btwn KClO3 and O2 is 2:3
the 2=x moles of KClO3 the 3 = 7.81 mol of O2
15.62=3x 15.62/3= x
cross multiplying to get 5.21 moles =# of moles of KClO3 req.
,if 14.67g of C2H6 is allowed to react with 39.51g of O2 as shown what
would be the limiting reactant
molar mass (g/mole)
C2H6= 30.08, O2= 31.998, H2O= 18.015, CO2= 44.08
2C2H6 + 7O2 -> 6H2O + 4CO2 - correct answer -O2. in order to consume
all the C2H6 we would need 54.62g of O2, we only have 39.51g
what is the maximum amount of product that can be made in a
chemical reaction - correct answer -theoretical yield is calculated by
assuming that all the limited reagent is converted to product
when 10g of copper and 10g of iodine are mixed, 5g of Cul are made.
What is the percent yield of Cul? the theoretical yield is 15g
2Cu+ I2 -> 2Cul - correct answer -33%
percent yield= actual yield/ theoretical yield x 100. If 5g are produced,
then the percent yield is (5g/ 15g) x 100= 33%
describe the study of mass relationships btwn reactants and products in
a chemical reaction - correct answer -quantitative relation btwn the
, number of moles and mass of various products and reactants in a
chemical reaction
calculate the limiting reactant in the chemical equation , knowing that
3.25g of NH3 reacts with 3.50g of O2
4NH3 (g) + 5O2 (g) -> 4NO (g) + 6H2O (l) - correct answer -O2.
4 NH3+5O2 -> 4 NO+6H2O
3.25g of NH3= 3.25g/ 17g mol-1 = 0.19 mol of NH3.
available mass of O2 is 3.50 or
3.50g/32 mol-1 =0.11 mol of O2.
Since (0.11 mol) is less than NH3 (0.19 mol) , the limiting reagent is O2
what is the theoretical yield - correct answer -maximum amount of
product that can be formed in a chemical reaction. Formed based on
the amount of limiting reactant in a chemical reaction
45.599g of phosphorous (P4) were allowed to react w/ 67.900g of
oxygen (O2). If 95.201g of P4O10 were actually produced in the lab
what is the percent yield (%yield=actual yield/theoretical yield x 100)
