61. Which of the following chemical equation is incorrectly balanced ?
A. \(Sb_{2}S_{3}+12HCl\rightarrow 2H_{3}SbCl_{6}+3H_{2}S\)
B. \(3IBr+4NH_{3}\rightarrow NI_{3}+3NH_{4}Br\)
C. \(2KrF_{2}+2H_{2}O\rightarrow 2Kr+2O_{2}+4HF\)
D. \(PCl_{3}+3H_{2}O\rightarrow H_{3}PO_{3}+3HCl\)
Answer : Option C
Match the following
Column -I Column -II
(i) \(Cl_{2}O_{3}\) (P) basic anhydride
(ii) \(Li_{2}O\) (Q) acid anhydride
(iii) \(CO_{2}\) (R) base
A. (i) - (q) (ii) - (p) (iii) - (q)
B. (i) - (r) (ii) - (q) (iii) - (p)
C. (i) - (p) (ii) - (q) (iii) - (r)
D. (i) - (p) (ii) - (q) (iii) - (p)
Answer : Option A
63. How many g of NaOH can be obtained by reaction of 1 Kg of \(Na_{2}CO_{3}\) with \(Ca(OH)_{2}\) ?
64. How much calcium oxide (CaO) can be obtained by heating 200 Kg of lime stone that is 95% pure \(CaCO_{3}\) ?
65. Calculate the amount of NaOH required to neutralize 100 mL 0.1M \(H_{2}SO_{4}\)
A. 40 g
B. 0.4 g
C. 80 g
D. 0.8 g
Answer : Option D
Explanation :
→ 0.1M \(H_{2}SO_{4}\) = 1000 mL solution contains 0.1 mol \(H_{2}SO_{4}\)
\(\therefore \) 100 mL solution contains 0.01 mol \(H_{2}SO_{4}\)
→ \(\therefore \) mass of \(H_{2}SO_{4}\) = 0.01 x 98 = 0.98 g
\(2NaOH+H_{2}SO_{4}\rightarrow Na_{2}SO_{4}+2H_{2}O\)
2(40)g 98g
(?) \(\therefore \) 0.98g
= \(\frac{80\times 0.98}{98}\)
= 0.8 g
66. 3g of an oxide of a metal is converted into chloride and it yielded 5 g of chloride. Find the equivalent weight of the metal.
A. 33.25
B. 3.325
C. 12
D. 20
Answer : Option A
Explanation :
→ \(\frac{Wt\ of\ metal\ oxide}{Wt\ of\ metal\ Choride}\) = \(\frac{Eq\ wt\ of\ metal+Eq\ wt\ of\ oxide}{Eq\ wt\ of\ metal+Eq\ wt\ of\ Choride}\)
\(\therefore \frac{3}{5}=\frac{E+8}{E+35.5}\)
\(\therefore E=33.25\)
67. A compound contains two oxygen atoms, four carbon atoms and number of hydrogen atoms is double of carbon atoms. What is the density of vapour of this compound ?
A. 88
B. 44
C. 132
D. 72
Answer : Option B
Explanation :
→ M.F. \(C_{4}H_{8}O_{2}\)
\(\therefore \) Molar mass = 88
\(\therefore \) Vapour density = \(\frac{88}{2}\) =44
68. The number of molecules in 100 mL of each of \(O_{2}\), \(NH_{3}\) and \(CO_{2}\) at STP are
A. \(CO_{2} < O_{2} < NH_{3}\)
B. \(NH_{3} < O_{2} < CO_{2}\)
C. \(NH_{3} = CO_{2} < O_{2}\)
D. \(NH_{3} = CO_{2} = O_{2}\)
Answer : Option D
Explanation :
→ Equal volumes under identical conditions contain equal no. of molecules
69. Which of the following represents the formula of a compound which contains 26% nitrogen and 74% oxygen ?
A. \(N_{2}O\)
B. \(NO\)
C. \(NO_{2}\)
D. \(N_{2}O_{5}\)
Answer : Option D
Explanation :
\(N_{\frac{26}{14}}O_{\frac{74}{16}}\) = \(N_{1.85}O_{4.625}\) = \(N_{2}O_{5}\)
70. \(NKg^{-1}\) is the unit of
A. Momentum
B. Velocity
C. Pressure
D. Acceleration
Answer : Option D
Explanation :
→ \(F=ma\)
\(a=\frac{f}{m}=\frac{N}{Kg}=NKg^{-1}\)