Some Basic Concepts of Chemistry

For the following reaction, in the mass of water produced from 445 g of C57H110O6 is :
2C57H110O6(s) + 163 O2(g) \(\to\) 114 CO2(g) + 110 H2O(l)

For a reaction,
N2(g) + 3H2(g) \(\to\) 2NH3(g) ;
identify dihydrogen (H2) as a limiting reagent
in the following reaction mixtures.

What would be the molality of 20% (mass/
mass) aqueous solution of KI?
(molar mass of KI = 166 g mol–1)

The percentage composition of carbon by mole
in methane is :

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

The mole fraction of a solvent in aqueous solution of a solute is 0.8. The molality (in mol kg–1
) of the
aqueous solution is :

5 moles of AB2 weigh 125 × 10–3
kg and 10 moles of A2B2 weigh 300 × 10–3
kg. The molar mass of A (MA)
and molar mass of B (MB) in kg mol are:

Thermal decomposition of a Mn compound (X) at 513 K results in compound Y, MnO2 and gaseous product.
MnO2 reacts with NaCl and concentrated H2O4 to give a pungent gas Z. X, Y and Z, respectively, are :

25 g of an unknown hydrocarbon upon burning produces 88 g of CO2 and 9 g of H2O. This unknown
hydrocarbon contains :

A 10 mg effervescent tablet containing sodium bicarbonate and oxalic acid releases 0.25 ml of CO2 at T = 298.15 K and p = 1 bar. If molar volume of CO2 is 25.0 L under such condition, what is the percentage of sodium bicarbonate in each tab...

An organic compound is estimated through Duma's method and was found to evolve 6 moles of CO2. 4 moles of H2O and 1 mole of nitrogen gas. The formula of the compound is :

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 solutions ?

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

At 300 K and 1 atmospheric pressure, 10 mL of a hydrocarbon required 55 mL of O2 for complete
combustion, and 40 mL of CO2 is formed. The formula of the hydrocarbon is :

The minimum amount of O2(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)

An unknown chlorohydrocarbon has 3.55% of chlorine. If each molecule of the hydrocarbon has one chlorine atom only; chlorine atoms present in 1 g of chlorohydrocarbon are :
(Atomic wt. of Cl = 35.5 u; Avogadro constant = 6.023 $$ \times $...

A sample of \(NaCl{O_3}\) 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 $$...

For per gram of reactant, the maximum quantity of N2 gas is produced in which of the following thermal decomposition reactions ?
(Given : Atomic wt. - Cr = 52 u, Ba = 137 u)

The ratio of mass percent of C and H of an organic compound (CXHYOZ) is 6 : 1. If one molecule of the above compound (CXHYOZ) contains half as much oxygen as required to burn one molecule of compound CXHY completely to CO2 and H2O. The empi...

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

Excess of NaOH (aq) was added to 100 mL of FeCl3 (aq) resulting into 2.14 g of Fe(OH)3 . The molarity of FeCl3 (aq) is :
(Given molar mass of Fe = 56 g mol−1 and molar mass of Cl = 35.5 g mol−1)

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
1H atoms are replaced by 2H atoms is:

1 gram of a carbonate (M2CO3) on treatment with excess HCl produces 0.01186 mole of CO2. The molar mass of M2CO3 in g mol–1 is:

The amount of arsenic pentasulphide that can be obtained when 35.5 g arsenic acid istreated with excess H2S in the presence of conc. HCl ( assuming 100% conversion) is :

An organic compound contains C, H and S. The minimum molecular weight of the
compound containing 8% sulphur is :
(atomic weight of S = 32 amu)

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?

The ratio of masses of oxygen and nitrogen in a particular gaseous mixture is 1 : 4. The ratio of number of
their molecule is:

Experimentally it was found that a metal oxide has formula M0.98O. Metal M, present as M2+ and M3+ in its oxide. Fraction of the metal which exists as M3+ would be

A gaseous hydrocarbon gives upon combustion 0.72 g of water and 3.08 g of CO2. The empirical formula of the hydrocarbon is

The molarity of a solution obtained by mixing 750 mL of 0.5 (M) HCl with 250 mL of 2(M) HCl will be:

The density of a solution prepared by dissolving 120 g of urea (mol. Mass = 60 u ) in 1000g of water is
1.15 g/mL. The molarity of this solution is :

A 5.2 molal aqueous solution of methyl alcohol, CH3OH, is supplied. What is the mole fraction of methyl
alcohol in the solution ?

The density (in g mL-1) of a 3.60 M sulphuric acid solution that is 29% H2SO4 (molar mass = 98 g mol-1) by mass will be

In the reaction
2Al(s) + 6HCl(aq) \(\to\) 2Al3+ (aq) + 6Cl-(aq) + 3H2(g)

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

How many moles of magnesium phosphate Mg3(PO4)2 will contain 0.25 mole of oxygen atoms?

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 the substance will

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?

The ammonia evolved from the treatment of 0.30 g of an organic compound for the estimation of nitrogen was passed in 100 mL of 0.1 M sulphuric acid. The excess of acid required 20 mL of 0.5 M sodium hydroxide solution for complete neutraliz...

6.02 \(\times\) 1020 molecules of urea are present in 100 ml of its solution. The concentration of urea solution is (Avogadro constant, NA = 6.02 \(\times\) 1023 mol-1)

To neutralise completely 20 mL of 0.1 M aqueous solution of phosphorous acid (H3PO3), the volume of 0.1 M aqueous KOH solution required is

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

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?

Number of atoms in 558.5 gram Fe (at. wt. of Fe = 55.85 g mol-1) is

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

With increase of temperature, which of these changes?