Chapter: Basic Concept of Chemistry

A solution of two components containing \(\begin{align}{{n}_{1}}\end{align}\) moles of the \(\begin{align}{{1}^{{st}}}\end{align}\) component and \(\begin{align}{{n}_{2}}\end{align}\) moles of the \(\begin{align}{{2}^{{nd}}}\end{align}\) component is prepared. \(\begin{align}{{M}_{1}}\end{align}\) and \(\begin{align}{{M}_{2}}\end{align}\) are the molecular weights of component 1 and 2 respectively. If d is the density of the solution in g \(\begin{align}m{{L}^{{-1}}}\end{align}\), \(\begin{align}{{C}_{2}}\end{align}\) is the molarity and \(\begin{align}{{x}_{2}}\end{align}\) is the mole fraction of the \(\begin{align}{{2}^{{nd}}}\end{align}\) component, then \(\begin{align}{{C}_{2}}\end{align}\) can be expressed as:

The molarity of \(\begin{align}HN{{O}_{3}}\end{align}\) in a sample which has density 1.4 g/mL and mass percentage of 63% is ______. (Molecular Weight of \(\begin{align}HN{{O}_{3}}\end{align}\)= 63)

Amongst the following statements, that which was not proposed by Dalton was:

The percentage composition of carbon by mole in methane is:

8 g of NaOH is dissolved in 18 g of H₂O. Mole fraction of NaOH in solution and molality (in mol kg–1) of the solution respectively are:

The amount of sugar (C₁₂H₂₂O₁₁) required to prepare 2 L of its 0.1 M aqueous solution is:

An unknown chlorohydrocarbon has 3.55% of chlorine. If each molecule of the hydrocarbon has one chlorine atom only, chlorine atoms present in 1g of chlorohydrocarbon are: (Atomic wt. of Cl = 35.5u; Avogadro constant = \(\begin{align}6.023\times {{10}^{{23}}}\end{align}\)\(\begin{align}mo{{l}^{{-1}}}\end{align}\))

Excess of NaOH (aq) was added to 100 mL of \(\begin{align}FeC{{l}_{3}}\end{align}\) (aq) resulting into 2.14 g of \(\begin{align}Fe{{\left( {OH} \right)}_{3}}\end{align}\). The molarity of \(\begin{align}FeC{{l}_{3}}\end{align}\) (aq) is:
(Given molar mass of Fe=56 g \(\begin{align}mo{{l}^{{-1}}}\end{align}\) and molar mass of Cl=35.5 g \(\begin{align}mo{{l}^{{-1}}}\end{align}\))

5 L of an alkane requires 25 L of oxygen for its complete combustion. If all volumes are measured at constant temperature and pressure, the alkane is:

The molecular formula of a commercial resin used for exchanging ions in water softening is \(\begin{align}{{C}_{8}}{{H}_{7}}S{{O}_{3}}^{-}N{{a}^{+}}\end{align}\) (Mol. wt. 206. What would be the maximum uptake of \(\begin{align}C{{a}^{{2+}}}\end{align}\) ions by the resin when expressed in mole per gram resin?

Dissolving 120 g of a compound of (mol. wt. 60) in 1000 g of water gave a solution of density 1.12 g/mL. The molarity of the solution is:

The amount of oxygen in 3.6 moles of water is:

The density of 3M solution of sodium chloride is 1.252 g \(\begin{align}m{{L}^{{-1}}}\end{align}\). The molality of the solution will be: (molar mass, NaCl = 58.5 g \(\begin{align}mo{{l}^{{-1}}}\end{align}\))

Number of atoms in the following samples of substances is the largest in:

10 mL of 2(M) NaOH solution is added to 200 mL of 0.5 (M) of NaOH solution. What is the final concentration?

6 litres of an alkene require 27 litres of oxygen at constant temperature and pressure for complete combustion. The alkene is:

The concentrated sulphuric acid that is peddled commercial is 95% \(\begin{align}{{H}_{2}}S{{O}_{4}}\end{align}\) by weight. If the density of this commercial acid is 1.834 g \(\begin{align}c{{m}^{{-3}}}\end{align}\), the molarity of this solution is

The ratio of number of oxygen atoms (O) in 16.0 g ozone (\(\begin{align}{{O}_{3}}\end{align}\)), 28.0 g carbon monoxide (CO) and 16.0 oxygen (\(\begin{align}{{O}_{2}}\end{align}\)) is (Atomic mass: C = 12, O = 16 and Avogadro’s constant \(\begin{align}{{N}_{A}}=\text{ }6.0\text{ }\times {{10}^{{23}}}mo{{l}^{{-1}}}\end{align}\))

The ppm level of \(\begin{align}{{F}^{-}}\end{align}\) in a 500 g sample of a tooth paste containing 0.2 g \(\begin{align}{{F}^{-}}\end{align}\) is

5 g of benzene on nitration gave 6.6 g of nitrobenzene. The theoretical yield of the nitrobenzene will be

How many moles of magnesium phosphate, \(\begin{align}M{{g}_{3}}{{\left( {P{{O}_{4}}} \right)}_{2}}\end{align}\) will contain 0.25 mole of oxygen atoms?

Density of a 2.05M solution of acetic acid in water is 1.02 g/mL. The molality of the solution is

Two solutions of a substance (non electrolyte) are mixed in the following manner: 480 mL of 1.5 M first solution + 520 mL of 1.2 M second solution. What is the molarity of the final mixture?

If we consider that 1/6, in place of 1/12, mass of carbon atom as the relative atomic mass unit, the mass of one mole of the substance will

\(\begin{align}6.02\times {{10}^{{20}}}\end{align}\) molecules of urea are present in 100 ml of its solution. The concentration of urea solution is

25mL of a solution of barium hydroxide on titration with a 0.1 molar solution of hydrochloric acid gave a litre value of 35mL. The molarity of barium hydroxide solution was

With increase of temperature, which of these changes?

Number of atoms in 558.5 gram Fe (at. wt. of Fe = 55.85 g \(\begin{align}mo{{l}^{{-1}}}\end{align}\)) is

29. The average molar mass of chlorine is 35.5 g mol–1. The ratio of \(\begin{align}^{{35}}Cl\end{align}\) to \(\begin{align}^{{37}}Cl\end{align}\) in naturally occrring chlorine is close to:

The ratio of the mass percentages of ‘C & H’ and ‘C & O’ of a saturated acyclic organic compound ‘X’ are 4: 1 and 3: 4 respectively. Then, the moles of oxygen gas required for complete combustion of two moles of organic compound ‘X’ is _________.

The ratio of mass percent of C and H of an organic compound (\(\begin{align}{{C}_{X}}{{H}_{Y}}{{O}_{Z}}\end{align}\)) is 6: 1. If one molecule of the above compound (\(\begin{align}{{C}_{X}}{{H}_{Y}}{{O}_{Z}}\end{align}\)) contains half as much oxygen as required to burn one molecule of compound \(\begin{align}{{C}_{X}}{{H}_{Y}}\end{align}\) completely to \(\begin{align}C{{O}_{2}}\end{align}\)and \(\begin{align}{{H}_{2}}O\end{align}\). The empirical formula of compound \(\begin{align}{{C}_{X}}{{H}_{Y}}{{O}_{Z}}\end{align}\) is:

The most abundant elements by mass in the body of a healthy human adult are:
Oxygen (61.4%); Carbon (22.9%), Hydrogen (10.0%); and Nitrogen (2.6%). The weight which a 75 kg person would gain if all \(\begin{align}^{1}H\end{align}\) atoms are replaced by \(\begin{align}^{2}H\end{align}\) atoms is

What quantity (in mL) of a 45% acid solution of a monoprotic strong acid must be mixed with a 20% solution of the same acid to produce 800 mL of a 29.875% acid solution?

At 300 K and 1 atm, 15 mL of a gaseous hydrocarbon requires 375 mL air containing 20% \(\begin{align}{{O}_{2}}\end{align}\) by volume for complete combustion. After combustion the gases occupy 330 mL. Assuming that the water formed is in liquid form and the volumes were measured at the same temperature and pressure, the formula of the hydrocarbon is:

In Carius method of estimation of halogens, 250 mg of an organic compound gave 141 mg of AgBr. The percentage of bromine in the compound is:  (at. mass Ag =108; Br = 80)

Choose the incorrect formula out of the four compounds for an element X below:

A gaseous compound of nitrogen and hydrogen contains 12.5% (by mass) of hydrogen. The density of the compound relative to hydrogen is 16. The molecular formula of the compound is:

The amount of \(\begin{align}BaS{{O}_{4}}\end{align}\) formed upon mixing 100 mL of 20.8% \(\begin{align}BaC{{l}_{2}}\end{align}\) solution with 50 mL of 9.8% \(\begin{align}{{H}_{2}}S{{O}_{4}}\end{align}\) solution will be: (Ba = 137, Cl = 35.5, S = 32, H = 1 and O = 16)

A gaseous hydrocarbon gives upon combustion 0.72 g of water and 3.08 g. of \(\begin{align}C{{O}_{2}}\end{align}\). The empirical formula of the hydrocarbon is:

A transition metal M forms a volatile chloride which has a vapour density of 94.8. If it contains 74.75% of chlorine the formula of the metal chloride will be

In a compound C, H and N atoms are present in 9: 1: 3.5 by weight. Molecular weight of compound is 108. Molecular formula of compound is

The minimum number of moles of \(\begin{align}{{O}_{2}}\end{align}\) required for complete combustion of 1 mole of propane and 2 moles of butane is ______.

The volume, in mL, of 0.02 M \(\begin{align}{{K}_{2}}C{{r}_{2}}{{O}_{7}}\end{align}\) solution required to react with 0.288 g of ferrous oxalate in acidic medium is _________. (Molar mass of Fe = 56 g\(\begin{align}mo{{l}^{{-1}}}\end{align}\))

A 20.0 mL solution containing 0.2 g impure \(\begin{align}{{H}_{2}}{{O}_{2}}\end{align}\) reacts completely with 0.316 g of \(\begin{align}KMn{{O}_{4}}\end{align}\) in acid solution. The purity of \(\begin{align}{{H}_{2}}{{O}_{2}}\end{align}\) (in%) is __________ (mol. wt. of \(\begin{align}{{H}_{2}}{{O}_{2}}\end{align}\) = 34; mol. wt. of \(\begin{align}KMn{{O}_{4}}\end{align}\) = 158)

The mass of ammonia in grams produced when 2.8 kg of dinitrogen quantitatively reacts with 1 kg of dihydrogen is __________.

A 100 mL solution was made by adding 1.43 g of \(\begin{align}N{{a}_{2}}C{{O}_{3}}.x{{H}_{2}}O\end{align}\). The normality of the solution is 0.1 N. The value of x is _____________.

The mole fraction of glucose (\(\begin{align}{{C}_{6}}{{H}_{{12}}}{{O}_{6}}\end{align}\)) in an aqueous binary solution is 0.1. The mass percentage of water in it, to the nearest integer, is ________.

\(\begin{align}6.023\times {{10}^{{22}}}\end{align}\) molecules are present in 10 g of a substance 'x'. The molarity of a solution containing 5 g of substance 'x' in 2 L solution is _________ × \(\begin{align}{{10}^{{-3}}}\end{align}\).

The volume (in mL) of 0.1 N NaOH required to neutralise 10 mL of 0.1 N phosphinic acid is _________.

10.30 mg of \(\begin{align}{{O}_{2}}\end{align}\) is dissolved into a litre of sea water of density 1.03 g/mL. The concentration of \(\begin{align}{{O}_{2}}\end{align}\) in ppm is _____.

Ferrous sulphate heptahydrate is used to fortify foods with iron. The amount (in grams) of the salt required to achieve 10 ppm of iron in 100 kg of wheat is ______.Atomic weight: Fe = 55.85; S = 32.00; O = 16.00

\(\begin{align}{{NaClO}_{3}}\end{align}\) is used, even in spacecrafts, to produce \(\begin{align}{{O}_{2}}\end{align}\). The daily consumption of pure \(\begin{align}{{O}_{2}}\end{align}\) by a person is 492 L at 1 atm, 300 K. How much amount of NaCl\(\begin{align}{{O}_{3}}\end{align}\), in grams, is required to produce \(\begin{align}{{O}_{2}}\end{align}\) for the daily consumption of a person at 1 atm, 300 K? ________. \(\begin{align}NaCl{{O}_{3}}\left( s \right)\text{ }+\text{ }Fe\left( s \right)~\to {{O}_{2}}\left( g \right)\text{ }+\text{ }NaCl\text{ }\left( s \right)\text{ }+\text{ }FeO\left( s \right)\text{ }R\text{ }=\text{ }0.082~Latmmo{{l}^{{-1}}}{{K}^{{-1}}}\end{align}\)

The ammonia (\(\begin{align}N{{H}_{3}}\end{align}\)) released on quantitative reaction of 0.6 g urea (\(\begin{align}N{{H}_{2}}CON{{H}_{2}}\end{align}\)) with sodium hydroxide (NaOH) can be neutralized by:

5 moles of \(\begin{align}A{{B}_{2}}\end{align}\) weigh \(\begin{align}125\text{ }\times ~{{10}^{{-3}}}\end{align}\)kg and 10 moles of \(\begin{align}{{A}_{2}}{{B}_{2}}\end{align}\) weigh \(\begin{align}300\times ~{{10}^{{-3}}}\end{align}\)kg. The molar mass of A (\(\begin{align}{{M}_{A}}\end{align}\)) and molar mass of B (\(\begin{align}{{M}_{B}}\end{align}\)) in kg\(\begin{align}mo{{l}^{{-1}}}\end{align}\) are:

The minimum amount of \(\begin{align}{{O}_{2}}\end{align}\) (g) consumed per gram of reactant is for the reaction: (Given atomic mass: Fe = 56, O = 16, Mg = 24, P = 31, C = 12, H = 1)

For a reaction, \(\begin{align}{{N}_{2}}\end{align}\) (g) + 3\(\begin{align}{{H}_{2}}\end{align}\) (g) \(\begin{align}\to \end{align}\)2 \(\begin{align}{{NH}_{3}}\end{align}\) (g); identify dihydrogen (\(\begin{align}{{H}_{2}}\end{align}\)) as a limiting reagent in the following reaction mixtures.

0.27 g of a long chain fatty acid was dissolved in 100\(\begin{align}c{{m}^{3}}\end{align}\) of hexane. 10 mL of this solution was added dropwise to the surface of water in a round watch glass. Hexane evaporates and a monolayer is formed. The distance from edge to centre of the watch glass is 10 cm. What is the height of the monolayer? [Density of fatty acid = 0.9 g\(\begin{align}c{{m}^{{-3}}}\end{align}\); p = 3]

50 mL of 0.5 M oxalic acid is needed to neutralize 25 mL of sodium hydroxide solution. The amount of NaOH in 50 mL of the given sodium hydroxide solution is:

A 10 mg effervescent tablet containing sodium bicarbonate and oxalic acid releases 0.25 mL of C\(\begin{align}{{O}_{2}}\end{align}\) at T = 298.15K and P = l bar. If molar volume of C\(\begin{align}{{O}_{2}}\end{align}\) is 25.0 L under such condition, what is the percentage of sodium bicarbonate in each tablet? [Molar mass of NaHC\(\begin{align}{{O}_{3}}\end{align}\)= 84 g\(\begin{align}mo{{l}^{{-1}}}\end{align}\)]

25 mL of the given HCl solution requires 30 mL of 0.1 M sodium carbonate solution. What is the volume of this HCl solution required to titrate 30 mL of 0.2 M aqueous NaOH solution?

For the following reaction the mass of water produced from 445 g of \(\begin{align}{{C}_{{57}}}{{H}_{{110}}}{{O}_{6}}\end{align}\) is:
\(\begin{align}~2~{{C}_{{57}}}{{H}_{{110}}}{{O}_{6}}\left( s \right)\text{ }+\text{ }163{{O}_{2}}~\left( g \right)\to ~114C{{O}_{2}}\left( g \right)\text{ }+\text{ }110O\left( 1 \right)\end{align}\)

A sample of NaCl\(\begin{align}{{O}_{3}}\end{align}\) 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 AgCl = 143.5 g\(\begin{align}mo{{l}^{{-1}}}\end{align}\))

1 gram of a carbonate (\(\begin{align}{{M}_{2}}C{{O}_{3}}\end{align}\)) on treatment with excess HCl produces 0.01186 mole of \(\begin{align}C{{O}_{2}}\end{align}\). The molar mass of \(\begin{align}{{M}_{2}}C{{O}_{3}}\end{align}\) in g\(\begin{align}mo{{l}^{{-1}}}\end{align}\) is:

The amount of arsenic pentasulphide that can be obtained when 35.5 g arsenic acid is treated with excess \(\begin{align}{{H}_{2}}S\end{align}\) in the presence of conc. HCl (assuming 100% conversion) is:

The volume of 0.1 N dibasic acid sufficient to neutralize 1 g of a base that furnishes 0.04 mole of \(\begin{align}O{{H}^{-}}\end{align}\) in aqueous solution is:

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 adsorbed (per gram of charcoal) is:

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)

\( A+2B+3C\rightleftharpoons A{{B}_{2}}{{C}_{3}}\)

Reaction of 6.0 g of A, 6.0 ×\(\begin{align}{{10}^{{23}}}\end{align}\) atoms of B, and 0.036 mol of C yields 4.8 g of compound \(\begin{align}A{{B}_{2}}{{C}_{3}}\end{align}\). If the atomic mass of A and C are 60 and 80 amu, respectively, the atomic mass of B is (Avogadro no. = 6 × \(\begin{align}{{10}^{{23}}}\end{align}\)):

An aqueous solution of oxalic acid dihydrate contains its 6.3 g in 250 mL. The volume of 0.1 N NaOH required to completely neutralize 10 mL of this solution

The molality of a urea solution in which 0.0100 g of urea, [\(\begin{align}{{\left( {N{{H}_{2}}} \right)}_{2}}\end{align}\) CO] is added to 0.3000 dm3 of water at STP is:

The density (in g m\(\begin{align}{{L}^{{-1}}}\end{align}\)) of a 3.60 M sulphuric acid solution that is 29% {{H}_{2}}S{{O}_{4}}\end{align}\) (molar mass = 98 g \(\begin{align}mo{{l}^{{-1}}}\end{align}\)) by mass will be

In the reaction,
\(\begin{align}2Al(s)+6HCl(aq)\to 2A{{l}^{{3+}}}(aq)+6C{{l}^{-}}(aq)+3{{H}_{2}}(g)\end{align}\)

To neutralise completely 20 mL of 0.1 M aqueous solution of phosphorous acid (\(\begin{align}{{H}_{3}}P{{O}_{3}}\end{align}\)), the value of 0.1 M aqueous KOH solution required is

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?