HSC Science (Computer Science) १२ वीं कक्षा - Maharashtra State Board Question Bank Solutions for Chemistry

Write two applications of fuel cells.

Explain the aldol condensation of ethanal.

Define and explain the term, enthalpy of reaction.

Isotonic solutions are the solutions having the same ______.

Calculate the standard enthalpy of the reaction, \[\ce{SiO2_{(s)} + 3C_{(graphite)} -> SiC_{(s)} + 2CO_{(g)}}\] from the following reactions:

1. \[\ce{Si_{(s)} + O2_{(g)} -> SiO2_{(s)}}\], Δ_rH⁰ = −911 kJ
2. \[\ce{2C_{(graphite)} + O2_{(g)} -> 2CO_{(g)}}\], Δ_rH⁰ = −221 kJ
3. \[\ce{Si_{(s)} + C_{(graphite)} -> SiC_{(s)}}\], Δ_rH⁰ = −65.3 kJ

A solution containing 10 g glucose has osmotic pressure 3.84 atm. If 10 g more glucose is added to the same solution, what will be its osmotic pressure? (Temperature remains constant)

\[\ce{XeF6 + H2O ->[Partial][Hydrolysis] \underline{}\underline{}\underline{}\underline{} + \underline{}\underline{}\underline{}\underline{}}\]

\[\ce{XeF4 + H2O - \underline{}\underline{}\underline{}\underline{} + \underline{}\underline{}\underline{}\underline{}}\]

Which of the following reactions defines the enthalpy of formation?

Standard enthalpy of combustion of a substance is given. Then Write thermochemical equation.

Δ_cH⁰[C₂H₅OH(1)] = - 1409 kJ mol^-1

Standard enthalpy of combustion of a substance is given. Then Write thermochemical equation.

Δ_cH⁰[CH₃CHO(l)] = - 1166 kJ mol^-1

When acetaldehyde is treated with dilute NaOH, the following reaction is observed.

\[\begin{array}{cc}
\ce{2CH3 - CHO ->[dil.NaOH] CH3 - CH - CH2 - CHO}\\
\phantom{...............}|\\
\phantom{.................}\ce{OH}
\end{array}\]

1. What are the functional groups in the product?
2. Can another product be formed during the same reaction? (Deduce the answer by doing atomic audit of reactant and product).
3. Is this an addition reaction or condensation reaction?

Heat of combustion of methane is - 890 kJ/mol. On combustion of 12 gm of methane in excess of oxygen, ______ heat is evolved.

For the reaction, aA + bB → cC + dD, write the expression for enthalpy change of reaction in terms of enthalpies of formation of reactants and products.

The enthalpy of combustion of S (rhombic) is − 297 kJ mo1^-1. Calculate the amount of sulphur required to produce 29. 74 kJ of heat.

Define the term common ion effect. Explain with suitable example.

Draw energy profile diagram and show:

1. activated complex
2. energy of activation for forward and backward reactions
3. enthalpy of reaction

The heat evolved in the combustion of 6.022 x 10²¹ carbon particles is 3.94 kJ. The heat of combustion of carbon is ______.

For the reaction, H₂ + I₂ ⇌ 2HI; ΔH = 12.4 kcal. The heat of formation of HI, ΔH_f = ______.

NICAD storage cell is made up of ______ electrodes.