HSC Science (General) १२ वीं कक्षा - Maharashtra State Board Question Bank Solutions

Calculate emf of the following cell at 25 °C :

Fe|Fe²⁺(0.001 M)| |H⁺(0.01 M)|H₂(g) (1 bar)|Pt (s)

E°(Fe²⁺| Fe)= −0.44 V E°(H⁺ | H₂) = 0.00 V

A first order reaction takes 30 minutes for 50% completion. Calculate the time required for 90% completion of this reaction.

(log 2 = 0.3010)

Write the hybridization and shape of the following complexe : [CoF₆]^3–

(Atomic number : Co = 27, Ni = 28)

Write the hybridization and shape of the following complexe : [Ni(CN)₄]^2–

^{(Atomic number : Co = 27, Ni = 28)}

Calculate the freezing point of the solution when 31 g of ethylene glycol (C₂H₆O₂) is dissolved in 500 g of water.

(K_f for water = 1.86 K kg mol^–1)

Calculate e.m.f. and ∆G for the following cell:

Mg (s) |Mg²⁺ (0.001M) || Cu²⁺ (0.0001M) | Cu (s)

`"Given :" E_((Mg^(2+)"/"Mg))^0=−2.37 V, E_((Cu^(2+)"/"Cu))^0=+0.34 V.`

Draw the structure of: Pyrophosphoric acid

Write the electronic configuration of the following elements:

Sulphur (Z = 16)

When primary amine reacts with CHCl3 in alcoholic KOH, the product is _______.

(A) aldehyde

(B) alcohol

(C) cyanide

(D) an isocyanide

In the representation of the galvanic cell, the ions in the same phase are separated by a _______.

The unit of rate constant for zero order reaction is _______.

(A) t^–1

(B) mol dm^–3 t^–1

(C) mol^–1 dm³ t^–1

(D) mol^–2 dm⁶ t^–1

Define enzymes.

Which among the following reactions is an example of a zero order reaction?

a) `H_(2(g)) + I_(2(g)) -> 2HI_(g)`

b) `2H_2O_(2(l)) -> 2H_2O_(l) + O_(2(g))`

c) `C_12H_22O_(11(aq)) + H_2O_(l) -> C_6H_12O_(6(aq)) + C_6H_12O_(6(aq))`

d) `2NH_(3g)`   `N(2g) + 3H_(2(g))`

Define Freezing point.

3.795 g of sulphur is dissolved in 100g of CS₂. This solution boils at 319.81 K. What is the molecular formula of sulphur in solution? The boiling point of CS₂ is 319.45 K. (Given that K_b for CS₂ = 2.42 K kg mol^-1 and atomic mass of S = 32)

What is the action of following reagents on glucose?

bromine water

What is the action of following reagents on glucose?

dilute HNO₃

What is the action of following reagents on glucose?

hydroxyl amine

What is the action of Benzene Sulphonyl Chloride on primary, secondary and tertiary
amines?

Draw the structure of H₄P₂O₆ hypophosphoric acid