HSC Science (Electronics) 12th Standard Board Exam - Maharashtra State Board Question Bank Solutions

Calculate the packing efficiency for bcc lattice.

In case of hcp structure, how are spheres in first, second and third layers arranged?

A substance crystallizes in fcc structure. The unit cell edge length is 367.8 pm. Calculate the molar mass of the substance if its density is 21.5 g/cm³.

The following solution/solvent has maximum vapour pressure _______.

According to Raoult’s law, relative lowering of vapour pressure of solution containing dissolved nonvolatile solute _______.

Write the expression for relative lowering of vapour pressure.

The vapour pressure of a pure liquid is 0.043 bar at a certain temperature. When a nonvolatile solute is dissolved into it, the vapour pressure of the solution is found to be 0.041 bar. What is the relative lowering of vapour pressure?

For a very dilute solution, the osmotic pressure is given by π = n₂RT/V where V is the volume in L containing n₂ moles of nonvolatile solute. Establish the equation for molar mass of solute.

Give two points to explain why vapour pressure of solvent is lowered by dissolving nonvolatile solute into it.

NH₄F is a salt of weak acid HF (K_a = 7.2 × 10^–4) and weak base NH₄OH (K_b = 1.8 × 10^–5), the solution of NH₄F will be ______.

Give any one example of salt derived from weak acid and weak base.

Define Hydrolysis of salt.

Calculate `"E"_"cell"^0` for galvanic cell with electrodes Co/Co³⁺// Mn²⁺/Mn. 
`"E"_"Mn"^0` = - 1.18 V, `"E"_"Co"^0` = 1.82 V.

What is cell voltage?

Give the chemical composition present in the salt bridge.

What are the functions of a salt bridge in a galvanic cell?

Represent the galvanic cell from following overall cell reaction:

3Ni_(s) + 2Al³⁺ (1 M) → 3Ni²⁺(1 M) + 2Al_(s)

Calculate standard cell potential of following galvanic cell:

Zn/Zn²⁺(1 M) // Pb²⁺(1 M)/Pb. If `"E"_"Pb"^0` = 0.126 V and `"E"_"Zn"^0` = –0.763 V

Calculate the voltage of the cell Sn_(s) / Sn²⁺(0.02 M) // Ag⁺ (0.01 M) / Ag_(s) at 25 °C.

Given: `"E"_"Sn"^circ` = - 0.136, `"E"_"Ag"^circ` = 0.800 V

Calculate `"E"_"cell"^circ` of the following galvanic cell:

Mg_(s) / Mg²⁺(1 M) // Ag⁺ (1 M) / Ag_(s) if `"E"_"Mg"^circ` = – 2.37 V and `"E"_"Ag"^circ` = 0.8 V. Write cell reactions involved in the above cell. Also mention if cell reaction is spontaneous or not.