861.

${\mathrm{CaCO}}_{3 } \rightleftharpoons \mathrm{CaO} + {\mathrm{CO}}_2 \mathrm{reaction} \mathrm{in} \mathrm{lime} \mathrm{kiln} \mathrm{goes} \mathrm{to} \mathrm{completion} \mathrm{because}$:

• CaO does not react to CO₂  to give CaCO₃

• backward reaction is very low

• CO₂ formed escapes out

• None of the above

Consider the following reversible reaction at equilibrium:

${\text{2H}}_2\mathrm{O} \left(\mathrm{g}\right) \rightleftharpoons 2 {\mathrm{H}}_2\mathrm{O} \left(\mathrm{g}\right) + {\mathrm{O}}_2 \left(\mathrm{g}\right) ; \mathrm{\Delta H} = +24.7 \mathrm{KJ}$

The maximum decomposition of H₂O(g) will occur by which of the following change in conditions.

• Increasing temperature and decreasing pressure

• Decrease temperature and increasing pressure

• Increasing both temperature and pressure

• Increasing temperature at constant pressure

The pH of a 10^-10M - NaOH solution is

• 10

• 7.01

• 6.99

• 4

Which has minimum solubility?

• Bi₂S₃

• Ag₂S

• CoS

• PbS

NaOH(aq), HCl(aq), and NaCl(aq) concentration of each is 10^-3 M. Their pH will be respectively

• 10, 6, 2

• 11, 3, 7

• 10, 3, 7

• 10, 4, 7

On adding A to the reaction at equilibrium, AB (s) $\rightleftharpoons$ A(g) + B(g) the new equilibrium concentration of A becomes double, the equilibrium concentration of B would become:

• 1/2 of its original value

• 1/4 of its original value

• 1/8 of its original value

• Twice its original value

A solution contains 10 mL of 0.1 N NaOH and 10mL of 0.05 NH₂SO₄.pH of this solution is:

• zero

• less than 7

• greater than 7

• 7

Fear or excitement, generally cause one to breathe rapidly and it results in the decrease of concentration of CO₂ in blood. In what way it will change pH of blood?

• pH will increase

• pH will decrease

• No change

• pH will be 7

Which of the following acids is monobasic?

• H₃PO₃

• H₃PO₂

• H₂SO₃

• H₃PO₄

A litre solution containing NH₄Cl and NH₄OH has hydroxide ion concentration of 10^-6 mol L^-1. Which of the following hydroxide could be precipitated when the solution is added to 1L solution of 0.1M metal ions?

Ba(OH)₂ (Ksp = 5 x 10^-3)

Ni(OH)₂ (K_sp = 1.6 x 10^-16)

Mn(OH)₂ (K_sp = 2 x 10^-13) 

Fe(OH)₂ (K_sp = 8 x 10^-16)

• I and IV

• III and IV

• II and IV

• II , III and IV