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Limiting reagent, percent yield and percent excess

36 questions on Limiting reagent, percent yield and percent excess from the Mole Concept chapter: 8 NEET level, 14 JEE Main, 14 JEE Advanced. Each one opens with its answer and solution.

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For N2 + 3H2 -> 2NH3, 14 g of N2 and 6 g of H2 are mixed and allowed to react completely. Taking N=14, H=1, what mass of NH3 is formed? NEET level
Heating 50 g of pure CaCO3 (100 g/mol) gives CaO (56 g/mol) and CO2. If only 22.4 g of CaO is actually obtained, the percent yield is NEET level
In 2H2 + O2 -> 2H2O, 4 g of H2 is ignited with 24 g of O2 (H=1, O=16). What mass of which reactant is left over after complete reaction? NEET level
2.4 g of Mg (24 g/mol) is added to a solution containing 0.15 mol of HCl according to Mg + 2HCl -> MgCl2 + H2. The volume of H2 at STP is NEET level
For Fe2O3 + 3CO -> 2Fe + 3CO2, 100 g of Fe2O3 (160 g/mol) is heated with 56 g of CO (28 g/mol). Taking Fe=56 and complete reaction of the limiting reagent, the ... JEE Main level
6.35 g of Cu reacts with excess AgNO3 solution: Cu + 2AgNO3 -> Cu(NO3)2 + 2Ag. If 18.0 g of silver is collected, the percent yield is (Cu=63.5, Ag=108) JEE Main level
Propane burns as C3H8 + 5O2 -> 3CO2 + 4H2O. If air supplies oxygen 25% in excess of the stoichiometric requirement, how many moles of O2 are supplied per mole o... JEE Main level
Benzene (C6H6, 78 g/mol) is converted to nitrobenzene in 85% yield, and nitrobenzene is reduced to aniline (C6H7N, 93 g/mol) in 70% yield. Starting with 39 g of... JEE Main level
10.8 g of Al is burned in 8.0 g of O2: 4Al + 3O2 -> 2Al2O3. Taking Al=27, O=16, find the mass of Al2O3 formed in grams, to one decimal place. JEE Main level
32 g of SO2 and 12 g of O2 react as far as possible in 2SO2 + O2 -> 2SO3 (S=32, O=16). Find the mass in grams of the reactant left over, to one decimal place. JEE Main level
A limestone sample is 80% CaCO3 by mass (100 g/mol). 40.0 g of it is treated with excess dilute HCl and the CO2 is collected with an 85% yield. Find the volume ... JEE Main level
Ammonia is oxidised: 4NH3 + 5O2 -> 4NO + 6H2O. 3.4 g of NH3 (17 g/mol) is mixed with 6.4 g of O2 (32 g/mol) and the reaction goes to completion. The mass of wat... JEE Advanced level
11.5 g of Na reacts with 21.3 g of Cl2 in 2Na + Cl2 -> 2NaCl (Na=23, Cl=35.5). The percent excess of the reagent in excess (relative to its stoichiometric requi... JEE Advanced level
13.5 g of Al and 32.0 g of Fe2O3 (160 g/mol) react as 2Al + Fe2O3 -> Al2O3 + 2Fe, but the reaction proceeds only to 90% of the extent possible for the limiting ... JEE Advanced level
White phosphorus is burned: P4 + 5O2 -> P4O10, using 12.4 g of P4 (124 g/mol) and 12.8 g of O2. The P4O10 formed (the first step runs to completion, consuming t... JEE Advanced level
56 g of N2 and 18 g of H2 react as N2 + 3H2 -> 2NH3 with an actual yield of 80% based on the limiting reagent (N=14, H=1). Choose the correct statement(s). JEE Advanced level
13.0 g of zinc (65 g/mol) is added to 100 mL of 3.0 M HCl: Zn + 2HCl -> ZnCl2 + H2. Choose the correct statement(s). (Molar volume at STP 22.4 L/mol.) JEE Advanced level
17 g of NH3 and 48 g of O2 react as far as possible according to 4NH3 + 5O2 -> 4NO + 6H2O (N=14, O=16, H=1). Choose the correct statement(s). JEE Advanced level
28 g of N2 reacts with 10 g of H2 according to N2 + 3H2 -> 2NH3. The maximum mass of NH3 formed is (N = 14, H = 1) NEET level
In 2Mg + O2 -> 2MgO, 4.8 g of Mg is heated with 1.6 g of O2. The mass of MgO formed is (Mg = 24, O = 16) NEET level
50 g of CaCO3 is heated: CaCO3 -> CaO + CO2. If 21 g of CaO is actually obtained, the percentage yield is (Ca = 40, C = 12, O = 16) NEET level
4 mol of H2 is mixed with 3 mol of O2 for 2H2 + O2 -> 2H2O. The percentage of O2 in excess over the amount required is NEET level
Fe2O3 + 3CO -> 2Fe + 3CO2. When 240 g of Fe2O3 reacts with 84 g of CO, the maximum mass of Fe obtained is (Fe = 56, C = 12, O = 16) JEE Main level
5.4 g of Al reacts with 18.25 g of HCl: 2Al + 6HCl -> 2AlCl3 + 3H2. The volume of H2 at STP (22.4 L/mol) is (Al = 27, H = 1, Cl = 35.5) JEE Main level
10.6 g of Na2CO3 reacts with excess HCl and 3.96 g of CO2 is collected. The percentage yield of CO2 is (Na = 23, C = 12, O = 16) JEE Main level
6.4 g of CH4 is burned in 32 g of O2: CH4 + 2O2 -> CO2 + 2H2O. The percentage of O2 in excess over the stoichiometric requirement is (C = 12, H = 1, O = 16) JEE Main level
24.5 g of KClO3 is decomposed: 2KClO3 -> 2KCl + 3O2. If the yield is 85%, find the mass of O2 obtained in grams, to two decimals (K = 39, Cl = 35.5, O = 16). JEE Main level
20.0 g of Zn is added to 150 mL of 0.500 M H2SO4: Zn + H2SO4 -> ZnSO4 + H2. Find the volume of H2 at STP in litres (22.4 L/mol), to two decimals (Zn = 65). JEE Main level
For 4NH3 + 5O2 -> 4NO + 6H2O, 3.4 g of NH3 is mixed with 11.2 g of O2. Find the percentage of O2 in excess over the amount required for complete reaction of NH3... JEE Main level
64 g of sulfur is burnt to SO2 with 90% yield. The SO2 is then oxidised, 2SO2 + O2 -> 2SO3, with 75% yield. The mass of SO3 finally obtained is (S = 32, O = 16) JEE Advanced level
50.0 mL of 0.200 M BaCl2 is mixed with 100.0 mL of 0.150 M Na2SO4. Assuming complete precipitation of BaSO4 and additive volumes, the mass of precipitate and th... JEE Advanced level
12 g of carbon is burned in 20 g of O2, so that the products are only CO and CO2 and all the carbon and oxygen are consumed. Find the mass of CO formed in grams... JEE Advanced level
17.0 g of AgNO3 is mixed with 4.68 g of NaCl in water: AgNO3 + NaCl -> AgCl + NaNO3. If the isolated AgCl is 92% of the theoretical amount, find its mass in gra... JEE Advanced level
5.4 g of Al reacts with 10.65 g of Cl2: 2Al + 3Cl2 -> 2AlCl3 (Al = 27, Cl = 35.5). Select the correct statement(s). JEE Advanced level
For A + 2B -> C, a student mixes 0.50 mol of A with 0.80 mol of B and isolates 0.30 mol of C. Select the correct statement(s). JEE Advanced level
14.0 g of Fe and 6.4 g of S are heated to form FeS, and the cooled product (with any leftover reactant) is treated with excess dilute HCl: FeS + 2HCl -> FeCl2 +... JEE Advanced level