In an organic compound of molar mass 108 g mol-1 C, H and N atoms are present in 9 : 1 : 3.5 by weight. The molecular formula can be; A. C6H8N2 B. C7H10N C. C5H6N3 D. C4H18N3 Solution: (A) Given, Molar mass = 108 g/mol. Therefore, The mass of C present in one... View Article
A gaseous mixture contains CH4 and C2H6 in equimolecular proportion. The weight of 2.24 litres of this mixture at NTP is: A. 3 g B. 4.6 g C. 1.6 g D. 2.3 g Solution: (D) Mol wt of CH4 = 16 g/mol Mol wt of C2H6 = 30 g/mol Total = 46 g/mol ⇒1 Mol... View Article
An aqueous solution of 6.3 g oxalic acid dihydrate is made up to 250 mL. The volume of 0.1 N NaOH required to completely neutralize 10 mL of this solution is: A. 40 mL B. 20 mL C. 10 mL D. 4 mL Solution: (A) n-factor for H2C2O4.2H2O = 2 Normality = weight × 2 × 1000 / molecular weight... View Article
100 mL of 0.1N hypo decolourized iodine by the addition of x g of crystal copper sulphate to an excess of KI. The value of x is: A. 5.0 g B. 1.25 g C. 2.5 g D. 4 g Solution: (C) Let us first find the valence factor and write down the chemical reaction: 2CuSO4 +... View Article
n g of substance X reacts with m g of substance Y to form p g of substance R and q g of substance S. This reaction can be represented as X + Y = R + S. The relation which can be established in the amounts of the reactants and the products will be: A. n − m = p − q B. n + m = p + q C. n = m D. p = q Solution: (B) X + Y ⇌ R + S ng mg pg qg N + m = p + q considering... View Article
If the density of water is 1 g cm−3 then the volume occupied by one molecule of water is approximately; A. 18 cm3 B. 22400 cm3 C. 6.02 × 10−23 cm3 D. 3.0 × 10−23 cm3 Solution: (D) We know, Density = mass / volume... View Article
3.92 g of ferrous ammonium sulphate crystal are dissolved in 100 mL of water, 20 mL of this solution requires 18mL of potassium permanganate during titration for complete oxidation. The weight of KMnO4 present in one litre of the solution is: A. 34.76 g B. 12.38 g C. 1.238 g D. 3.476 g Solution: (D) Molecular weight of Ferrous ammonium sulphate ((NH4)2Fe(SO4)2.6H2O) = 392... View Article
2.6 g of a mixture of calcium carbonate and magnesium carbonate is strongly heated to the constant weight of 1.3 g. The atomic weights of calcium and magnesium are 40 and 24 respectively. State which of the following weights expresses the weight of calcium carbonate in the original mixture? A. 980 mg B. 400 mg C. 1.75 g D. 0.74 g Solution: (D) Let the weight of CaCO3 in mixture = x g Then weight of MgCO3 will be 2.6-x g... View Article
4.0g of caustic soda (molmass40) contains the same number of sodium ions as present in? A. 10.6 g of Na2CO3 (mol.mass 106) B. 58.5g of NaCl (formula mass 58.5) C. 100ml of 0.5MNa2SO4 (formula mass 142) D. 1mol of NaNO3... View Article
If isotopic distribution of C-12 and C-14 is 98% and 2% respectively, then the number of C-14 atoms in 12 g of carbon is; A. 1.032 × 1022 B. 3.01 × 1022 C. 5.88 × 1023 D. 6.02 × 1023 Solution: (A) 1 mole of carbon has NA molecules.... View Article
If 224 mL of a triatomic gas has a mass of 1 g at 273 K and 1 atm pressure, then the mass of one atom is; A. 8.30 × 0−23 g B. 6.24 × 10−23 g C. 2.08 × 10−23 g D. 5.54 × 10−23 g Solution: () No.... View Article
Among the following pairs of compounds, the one that illustrates the law of multiple proportions is: A. NH3 and NCl3 B. H2S and SO2 C. CuO and Cu2O D. CS2 and FeSO4 Solution: (C) If we recall the concept of law of multiple proportions... View Article
Assuming fully decomposed, the volume of CO2 released at STP on heating 9.85 g of BaCO3 (Atomic mass of Ba = 137) will be _____. A. 0.84 L B. 2.24 L C. 4.06 L D. 1.12 L Solution: (D) BaCO3 → BaO + CO2↑ Molecular weight of BaCO3 = 137 + 12 + (3 x 16)... View Article
The amount of zinc required to produce 224 mL of H2 at STP on treatment with dilute H2SO4 will be; A. 65 g B. 0.065 g C. 0.65 g D. 6.5 g Solution: () The reaction between zinc with sulfuric acid is given by the following formula. Zn... View Article
Dimensions of pressure are same as that of; A. Energy B. Energy per unit volume C. Force D. Force per unit volume Solution: (B) Dimension of Pressure, Pressure = F / A ⇒... View Article
Two containers P and Q of equal volume (1 litre each) contain 6 g of O2 and SO2 respectively at 300 K and 1 atmosphere, then; A. Number of molecules in P is less than that in Q B. Number of molecules in P and Q is same C. Number of molecules in Q is less than that... View Article
Rearrange the following (I to IV) in the order of increasing masses and choose the correct answer from (a), (b) ,(c) and (d) (Atomic mass :N = 14, O = 16, Cu = 63). I. 1 molecule of oxygen II. 1 atom of nitrogen III. 1 × 10-10 g molecular weight of oxygen IV. 1 × 10-10 g atomic weight of... View Article
How many millilitres (mL) of 1 M H2SO4 solution is required to neutralise 10 mL of 1 M NaOH solution? A. 2.5 B. 5.0 C. 10.0 D. 20.0 Solution: (B) The reaction is, H2SO4 + 2NaOH → Na2SO4+ 2H2O Using normality, 2 × MH2SO4... View Article
0.115 g of pure sodium metal was dissolved in 500 ml distilled water. The normality of the above solution, whose resulting volume is 400 ml, would be; A. 0.010 N B. 0.0115 N C. 0.0125 N D. 0.046 N Solution: (A) Weight of solute = 0.115 g The molecular mass of solute = 23 The volume... View Article
A 5 molar solution of H2SO4 is diluted from 1 litre to a volume of 10 litres, the normality of the solution will be; A. 1 N B. 0.1 N C. 5 N D. 0.5 N Solution: () N1V1 = N2V2 Given, molarity of H2SO4 = 5M, N1 = Molarity × basicity = 5 ×... View Article