20.0 g each of Fe2O3 and AI are mixed together and react according to the following equation.
What is the theoretical yield of Fe? Report your answer in grams, to three significant figures.
Fe2O3 (g) + 2AI(s) rightarrow AI2O3(s) + 2Fe(s) g Write a balanced net ionic equation for
the reaction between lead nitrate and sodium sulfate, in solution.. What is the molarity of a 1.30
L solution containing 6.00 g of NaCN? Report you to the correct number of significant figures.
M How many milliliters of 0.480 M NaOH would be required to titrate a 5.00 mL of 0.320
MH2SO4? Report your answer to the correct number of significant figures. mL. Write a
balanced chemical equation for the combustion of octane, C8H18. If the standard enthalpy of
formation (Delta Hf) of methanol,CH3OH, is - 238.6 kJ delta = - 394 kJ/mol, and Delta H
(H2O ) = 286 kJ/mol, calculate the combustion of methanol. Report your answer to the correct
number of significant. kJ/mol
Solution
1) 1 mole of Fe2O3 gives 2 moles of Fe
so
20/160 moles will give = 40/160 = 1/4 = .25 moles of Fe
so we get
56*.25 gm of Fe = 14 gm of Fe
2)Na2SO4 + Pb(NO3)2 ----> 2NaNO3 + PbSO4
3) 6 gm NaCN = 6/(49) moles of NaCN = .122 moles of NaCN
so Molarity = .122/1.3 = .0941 M
4)Let V volume be required so we get
V*0.48 = 2*5*.32
on solving we get
V = 6.67 mL
5) 2C8H18 + 25O2 ---> 16CO2 + 18H2O
What is the theoretical yield of Fe? Report your answer in grams, to three significant figures.
Fe2O3 (g) + 2AI(s) rightarrow AI2O3(s) + 2Fe(s) g Write a balanced net ionic equation for
the reaction between lead nitrate and sodium sulfate, in solution.. What is the molarity of a 1.30
L solution containing 6.00 g of NaCN? Report you to the correct number of significant figures.
M How many milliliters of 0.480 M NaOH would be required to titrate a 5.00 mL of 0.320
MH2SO4? Report your answer to the correct number of significant figures. mL. Write a
balanced chemical equation for the combustion of octane, C8H18. If the standard enthalpy of
formation (Delta Hf) of methanol,CH3OH, is - 238.6 kJ delta = - 394 kJ/mol, and Delta H
(H2O ) = 286 kJ/mol, calculate the combustion of methanol. Report your answer to the correct
number of significant. kJ/mol
Solution
1) 1 mole of Fe2O3 gives 2 moles of Fe
so
20/160 moles will give = 40/160 = 1/4 = .25 moles of Fe
so we get
56*.25 gm of Fe = 14 gm of Fe
2)Na2SO4 + Pb(NO3)2 ----> 2NaNO3 + PbSO4
3) 6 gm NaCN = 6/(49) moles of NaCN = .122 moles of NaCN
so Molarity = .122/1.3 = .0941 M
4)Let V volume be required so we get
V*0.48 = 2*5*.32
on solving we get
V = 6.67 mL
5) 2C8H18 + 25O2 ---> 16CO2 + 18H2O
