Stoichiometry:
Stoichiometry deals with the calculation of masses (sometimes volumes also) of the reactants and the products involved in a chemical reaction. Before understanding how to calculate the amounts of reactants required or the products produced in a chemical reaction, let us study what information is available from the balanced chemical equation of a given reaction.
Stoichiometric Calculations:
Step 1 Write down the correct formulas of reactants and products.
Step 2 Balance the number of atoms on both reactant and product sides.
Step 3 Make the equation balanced.
The coefficients of atoms or molecules are stoichiometric coefficients.
Limiting Reagent:
The reactant is consumed first in the reaction. When we are dealing with the balanced chemical equation, if the number of moles of reactants is not in the ratio of the stoichiometric coefficient of the balanced chemical equation, then there should be one reactant that should be limiting reactant.
% yield
Sometimes, experimentally, the reaction does not undergo 100% completion because of many factors which are involved in the actual industrial processes. So in such cases, we need the concept of % yield.
It is defined as the ratio of actual moles of product(s) formed to the number of moles that should have been theoretically formed assuming 100% completion of the reaction.
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JEE MAIN | Some basic concepts in chemistry |
The minimum amount of consumed per gram of reactant is for the reaction :
(Given atomic mass : , )
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For a reaction,
In which of the following reaction mixtures, H2 is limiting reagent?
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The ammonia released on the quantitative reaction of 0.6g, urea with sodium hydroxide can be neutralized by:
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How many moles of CaCO3 need to be heated to release 33.6 L of CO2 at STP?
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The formula of a gaseous hydrocarbon which requires 6 times of its own volume of for complete oxidation and produces 4 times its own volume of is The value of y is __________.
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Complete combustion of 1.80g of an oxygen containing compound gave 2.64 g of CO2 and 1.08 g of . The percentage of oxygen in the organic compound is:
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Complete combustion of 750 g of an organic compound provides 420 g of and 210 g of .The percentage composition of carbon and hydrogen in organic compound is 15.3 and ______respectively. (Round off to the Nearest Integer).
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_________ grams of 3-Hydroxy propanal (MW=74) must be dehydrated to produce 7.8 g of acrolein (MW = 56) (C3H4O) if the percentage yield is 64. (Round off to the Nearest Integer).
[Given : Atomic masses : C : 12.0 u, H : 1.0 u, O : 16.0 u ]
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The mass of ammonia in grams produced when 2.8 kg of dinitrogen quantitatively reacts with 1 kg of dihydrogen is_________
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The minimum number of moles of O2 required for complete combustion of 1 mole of propane and 2 moles of butane is ______
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If a rocket runs on fuel and liquid oxygen,the weight of oxygen required and released for every litre of fuel respectively are:
(Given: density of the fuel is )
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120 g of an organic compound that contains only carbon and hydrogen gives 330 g of , and 270 g of water on complete combustion, The percentage of carbon and hydrogen, respectively are
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On complete combustion of an organic compound gave of carbon dioxide and of water. The percentage of carbon in the given organic compound is ______________.(Nearest Integer)
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CNG is an important transportation fuel. When CNG is mixed with oxygen in vehicles, it leads to the formation of and and produces large quantity of heat during this combustion, then the amount of carbone dioxide, produced in grams is ____. [nearest integer]
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116g of a substance upon dissociation reaction, yields 7.5g of hydrogen, 60g of oxygen and 48.5g of carbon. Given that the atomic masses of H,O and C are 1,16 and 12, respectively. The data agrees with how many formulae of the following?
_______________.
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The complete combustion of 0.492 g of an organic compound containing 'C', 'H' and 'O' gives 0.793g of . The percentage of oxygen composition in the organic compound is __________.(nearest integer)
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Production of iron in a blast furnace follows the following equation
when are allowed to react then the amount of iron (in g) produced is:
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of nitrogen gas is mixed with excess of hydrogen gas and it is found that of ammonia gas is produced. The volume of unused nitrogen gas is found to be ___
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In the given reaction,
if one mole of each of X and Y with 0.05 mol of Z gives compound . (Given : Atomic masses of X, Y and Z are 10,20 and 30 amu, respectively.) The yield of is ____________ .(Nearest integer)
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Considering the above reaction, the limiting reagent of the reaction and the number of moles formed respectively are :
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Consider the reaction The amount of required to produce of is
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Consider the complete combustion of butane, the amount of butane utilized to produce of water is________ . (in nearest integer)
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of propane is completely reacted with of oxygen. The mole fraction of carbon dioxide in the resulting mixture is . The value of is____________.(Nearest integer)
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A sample of a hydrate of barium chloride weighing 61 g was heated until all the water of hydration is removed. The dried sample weighed 52 g. The formula of the hydrated salt is : (atomic mass, Ba=137 amu, Cl=35.5 amu)
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If we have 1 mole of P and 3 mole of Cl2, which one is the limiting reagent and how many moles of PCl3 are formed?
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A sample of is converted by heat to NaCl with a loss of 0.16 g of oxygen. The residue is dissolved in water and precipitated as AgCl. The mass of AgCl (in g) obtained will be : (Given: Molar mass of )
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The ratio of the masses percentages of and of a saturated acyclic organic compound are 4:1 and 3:4 respectively . Then , the moles of oxygen gas required for complete combustion of two moles of organic compound is_____________
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The above reaction is carried out in a vessel starting with partial pressure . When the reaction is complete, the total pressure in the reaction vessel is _____m bar. (Round off of the nearest integer).
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In bromination of Propyne, with Bromine - tetrabromopropane is obtained in yield. The amount of - tetrabromopropane obtained from of Bromine in this reaction is _________ (Nearest integer)
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A sample of polyhydric alcoholic compound of molar mass gave of gas at STP. The number of alcoholic hydrogens present in compound is ___________.
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The molecular formula of a commercial resin used for exchanging ions in water softening is C8H7SO3Na (Mol. wt. 206). What would be the maximum uptake of Ca2+ ions by the resin when expressed in mole per gram resin?
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3 g of activated charcoal was added to 50 mL of acetic acid solution (0.06N) in a flask. After an hour it was filtered and the strength of the filtrate was found to be 0.042 N. The amount of acetic acid (in mg) adsorbed (per gram of charcoal) is:
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What is ?
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How many moles of water are obtained when 3 moles of H2 react with 1 mole of O2?
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The molecular formula of a commercial resin used for exchanging ions in water softening is C8H7SO3Na (Mol. wt. 206). What would be the maximum uptake of Ca2+ ions by the resin when expressed in mole per gram resin?
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The volume (in ml) of 0.125 M required to quantitatively precipitate chloride ions in 0.3g of is:
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The electrophile, attacks the benzene ring to generate the intermediate complex. Of the following, which complex is of lowest energy ?
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If 0.3 moles of Mg are added to HCl container having 0.5 mole HCl, how many moles of H2 are produced?
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For per gram of reactant taken, the maximum quantity of N2 gas is produced in which of the following thermal decomposition reactions ?
(Given : Atomic wt. - Cr=52u, Ba=137u)
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A bottle of soft drink has dissolved in it. Assuming behaves as an ideal gas, the volume of the dissolved at STP is_____. (Nearest integer)
Given : At STP, molar volume of an ideal gas is
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When a hydrocarbon A undergoes complete combustion it requires 11 equivalents of oxygen and produces 4 equivalents of water. What is the molecular formula of A ?
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Assume carbon burns according to the following equation :
When 12 g carbon is burnt in 48 g of oxygen, the volume of carbon monoxide produced is STP [nearest integer]
[Given: Assume co as an ideal gas, the Mass of c is 12 g mol–1, the Mass of O is 16 g mol–1, and the molar volume of an ideal gas STP is 22.7 L mol–1]
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The above reaction was studied at by monitoring the concentration of in which initial concentration was and after half an hour became . The rate of production of is______ mol
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Find out the molarity of the compounds present in the final solution obtained on complete precipitation reaction between of and of
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of was treated with of . Calculate the mass of formed in the given mixture:
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$4 \mathrm{P}_4+5 \mathrm{S}_8 \longrightarrow 4 \mathrm{P}_4 \mathrm{~S}_{10}$
If $31 \mathrm{~g}$ of $\mathrm{P}_4 \& 64 \mathrm{~g} \;of \mathrm{~S}_8$ react according to given equation then Limiting reagent is: $\left[{ }^{31} \mathrm{P},{ }^{32} \mathrm{S}\right]$
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Stoichiometry deals with the calculation of masses of the reactants and the products involved in a chemical reaction.