# Chemical Arithmetic Stoichiometry Quiz

### Chemical Arithmetic – Stoichiometry practice quiz

Ques. The equivalent weight of phosphoric acid (H3PO4) in the reaction,

(a) 25
(b) 49
(c) 59
(d) 98

Ans. (d)

Ques. A compound possesses 8% sulphur by mass. The least molecular mass is
(a) 200
(b) 400
(c) 155
(d) 355

Ans. (b)

Ques. The law of multiple proportions was proposed by
(a) Lavoisier
(b) Dalton
(c) Proust
(d) Gay-Lussac

Ans. (b)

Ques. What volume of Hydrogen gas, at 273 K and 1 atm pressure will be consumed in obtaining 21.6 g of elemental boron (atomic mass = 10.8) from the reduction of boron trichloride by Hydrogen?
(a) 22.4 L
(b) 89.6 L
(c) 67.2 L
(d) 44.8 L

Ans. (c)

Ques. 1 L of N2 combines with 3 L of H2 to form 2L of NH3 under the same conditions. This illustrates the
(a) Law of constant composition
(b) Law of multiple proportions
(c) Law of reciprocal proportions
(d) Gay-Lussacâ€™s law of gaseous volumes

Ans. (d)

Ques. Calculate the weight of lime (CaO) that can be prepared by heating 200 g of limestone that is 95 % pure CaCO3.
(a) 160.4 g
(b) 206.2 g
(c) 360.2 g
(d) 106.4 g

Ans. (d)

Ques. The element similar to carbon is
(a) Mg
(b) Mn
(c) Sn
(d) Po

Ans. (c)

Ques. An astronaut receives the energy required per hour by the combustion of 34 g of sucrose present in his body. How much oxygen should he carry along with him for his energy requirement in a day ?
(a) 761.12
(b) 861.21
(c) 916.21
(d) 1016.12

Ans. (c)

Ques. One sample of atmospheric air is found to have 0.03% of carbon dioxide and another sample 0.04%. This is evidence that
(a) The law of constant composition is not always true
(b) The law of multiple proportions is true
(c) Air is a compound
(d) Air is a mixture

Ans. (d)

Related: p block important questions

Ques. Calculate the volume of hydrogen liberated at 27Â°C and 760 mm pressure by treating 0.6g of magnesium with excess of hydrochloric acid (given that 1 g of hydrogen occupies 11.2 litre at S.T.P. and Mg = 24)
(a) 2.216 L
(b) 1.651 L
(c) 1.850 L
(d) 0.615 L

Ans. (d)

Ques. One part of an element A combines with two parts of another B. Six parts of the element C combine with four parts of the element B. if A and C combine together the ratio of their weights will be governed by
(a) Law of definite proportion
(b) Law of multiple proportion
(c) Law of reciprocal proportion
(d) Law of conservation of mass

Ans. (c)

Ques. A solid element â€˜Xâ€™ has an atomic weight of 32 and burns in excess of oxygen to form a gaseous oxide â€˜Yâ€™. The volume after combustion is equal to the volume before combustion. The vapour density of â€˜Yâ€™ is 32. The number of atoms of oxygen that combine with one molecule of â€˜Yâ€™ are___.
(a) 4
(b) 2
(c) 1
(d) 3

Ans. (b)

Ques. The maximum amount of BaSO4 precipitated on mixing equal volumes of BaCl2 (0.5 M) with H2SO4 (1M) will correspond to
(a) 0.5 M
(b) 1.0 M
(c) 1.5 M
(d) 2.0 M

Ans. (a)

Ques. The number of significant figures in 6.02 x 1023 is
(a) 23
(b) 3
(c) 4
(d) 20

Ans. (b)

Ques. The number of equivalents of Na2S2O3 required for the volumetric estimation of one equivalent of Cu2+ is
(a) 1
(b) 2
(c) 3/2
(d) 3

Ans. (b)

Ques. A mixture of ZnCl2 and PbCl2 can be separated by
(a) Distillation
(b) Crystallization
(c) Sublimation

Ans. (b)

Ques. The number of moles of sodium oxide in 620 g of it is
(a) 1 mol
(b) 10 moles
(c) 18 moles
(d) 100 moles

Ans. (b)

Ques. 2.76 g of silver carbonate on being strongly heated yield a residue weighing
(a) 2.16 g
(b) 2.48 g
(c) 2.28 g
(d) 2.32 g

Ans. (a)

Ques. The volume occupied by 4.4 g of CO2 at STP is
(a) 22.4 L
(b) 2.24 L
(c) 0.224 L
(d) 0.1 L

Ans. (b)

Ques. What weight of SO2 can be made by burning sulphur in 5.0 moles of oxygen?
(a) 640 grams
(b) 160 grams
(c) 80 grams
(d) 320 grams

Ans. (d)

Ques. 12g of Mg (at. mass 24) on reacting completely with acid gives hydrogen gas, the volume of which at STP would be
(a) 22.4 L
(b) 11.2 L
(c) 44.8 L
(d) 6.1 L

Ans. (b)

Ques. To neutralise 20 ml of M / 10 sodium hydroxide, the volume of M / 20 hydrochloric acid required is
(a) 10 ml
(b) 15 ml
(c) 20 ml
(d) 40 ml

Ans. (d)

Ques. If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of a substance will
(a) Decrease twice
(b) Increase two fold
(c) Remain unchanged
(d) Be a function of the molecular mass of the substance

Ans. (c)

Ques. 30 ml of acid solution is neutralized by 15 ml of a 0.2 N base. The strength of acid solution is
(a) 0.1 N
(b) 0.15 N
(c) 0.3 N
(d) 0.4 N

Ans. (a)

Ques. Which one of the following properties of an element is not variable?
(a) Valency
(b) Atomic weight
(c) Equivalent weight
(d) All of these

Ans. (b)

Ques. In the preceeding question, the amount of Na2CO3 present in the solution is
(a) 2.650 g
(b) 1.060 g
(c) 0.530 g
(d) 0.265 g

Ans. (c)

Ques. After a chemical reaction, the total mass of reactants and products
(a) Is always increased
(b) Is always decreased
(c) Is not changed
(d) Is always less or more

Ans. (c)

Ques. If isobutane and n-butane are present in a gas, then how much oxygen should be required for complete combustion of 5 kg of this gas
(a) 17.9 kg
(b) 9 kg
(c) 27 kg
(d) 1.8 kg

Ans. (a)

Ques. What should be the weight of 50% HCl which reacts with 100 g of limestone?
(a) 50% pure
(b) 25% pure
(c) 10% pure
(d) 8% pure

Ans. (a)

Ques. A hydrocarbon contains 86% carbon, 488ml of the hydrocarbon weight 1.68 g at STP. Then the hydrocarbon is an
(a) Alkane
(b) Alkene
(c) Alkyne
(d) Arene

Ans. (b)

Ques. What will be the volume of CO2 at NTP obtained on heating 10 grams of (90% pure) limestone?
(a) 22.4 litre
(b) 2.016 litre
(c) 2.24 litre
(d) 20.16 litre

Ans. (b)

Ques. What volumes of nitrogen and hydrogen are required to produce 20 cc of ammonia gas at S.T.P.?
(a) 10cc, 30cc
(b) 10cc, 20cc
(c) 20cc, 30cc
(d) 15cc, 30cc

Ans. (a)

Ques. Equivalent weight of KMnO4 acting as an oxidant in acidic medium is
(a) The same as its molecular weight
(b) Half of its molecular weight
(c) One-third of its molecular weight
(d) One-fifth of its molecular weight

Ans. (d)

Ques. Under similar conditions of pressure and temperature, 40 ml of slightly moist hydrogen chloride gas is mixed with 20 ml of ammonia gas, the final volume of gas at the same temperature and pressure will be
(a) 100 ml
(b) 20 ml
(c) 40 ml
(d) 60 ml

Ans. (b)

Ques. 16.8 litre gas containing H2 and O2 is formed at NTP on electrolysis of water. What should be the weight of electrolysed water?
(a) 5 g
(b) 9 g
(c) 10 g
(d) 12 g

Ans. (b)

Ques. 1.5 mol of O2 combine with Mg to form oxide MgO. The mass of Mg (at. mass 24) that has combined is
(a) 72 g
(b) 36 g
(c) 48 g
(d) 24 g

Ans. (a)

Ques. The normality of orthophosphoric acid having purity of 70% by weight and specific gravity 1.54 would be
(a) 11 N
(b) 22 N
(c) 33 N
(d) 44 N

Ans. (a)

Ques. One part of an element A combines with two parts of another B. Six parts of the element C combine with four parts of the element B. if A and C combine together the ratio of their weights will be governed by
(a) Law of definite proportion
(b) Law of multiple proportion
(c) Law of reciprocal proportion
(d) Law of conservation of mass

Ans. (c)

Ques. M is the molecular weight of KMnO4. The equivalent weight of KMnO4 when it is converted into K2MnO4 is
(a) M
(b) M / 3
(c) M / 5
(d) M / 7

Ans. (a)