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

The rate constant for the first-order decomposition of H₂O₂ is given by the following equation:

`logk=14.2-(1.0xx10^4)/TK`

Calculate E_a for this reaction and rate constant k if its half-life period be 200 minutes.

(Given: R = 8.314 JK^–1 mol^–1)

The rate constant of a first order reaction increases from 2 × 10⁻² to 4 × 10⁻² when the temperature changes from 300 K to 310 K. Calculate the energy of activation (E_a).

(log 2 = 0.301, log 3 = 0.4771, log 4 = 0.6021)

What type of battery is mercury cell? Why is it more advantageous than dry cell?

An element with density 2.8 g cm^–3 forms a f.c.c. unit cell with edge length 4 x 10^–8 cm. Calculate the molar mass of the element.

(Given : N_A = 6.022 x 10²³ mol ^–1)

Name the type of cell which was used in Apollo space programme for providing electrical power.

Define terms: Fuel cell

Define the following terms: Secondary batteries

Which of the following pairs is an intensive property?

(A) Density, viscosity

(B) Surface tension, mass

(C) Viscosity, internal energy

(D) Heat capacity, volume

In the Arrhenius equation for a first order reaction, the values of ‘A’ of ‘E_a’ are 4 × 10¹³ sec⁻¹ and 98.6 kJ mol⁻¹ respectively. At what temperature will its half life period be 10 minutes?

[R = 8.314 J K⁻¹ mol⁻¹]

Which of the following is a basic oxide?

(A) SiO₂

(B) P₄O₁₀

(C) MgO

(D) Al₂O₃

55 L atm of work is obtained when 1.0 mole of an ideal gas is compressed isothermally from
a volume of 28.5 L to 18.5 L, the constant external pressure is

(A) 5.05 atm

(B) 5.5 atm

(C) 0.05 atm

(D) 0.55 atm

A metal crystallises into two cubic faces namely face centered (FCC) and body centered (BCC), whose unit cell edge lengths are 3.5 Å and 3.0 Å respectively. Find the ratio of the densities of FCC and BCC.

When phenol is heated with conc. HNO₃ in presence of conc. H₂SO₄ it yields _______.

(A) o-nitrophenol

(B) p-nitrophenol

(C) 2,4,6-trinitrophenol

(D) m-nitrophenol

Draw the structure of the chromate ion.

Which of the following compounds is used as a semipermeable membrane?

(a) Potassium ferrocyanide

(b) Potassium argentocyanide

(c) Sodium meta aluminate

(d) Copper ferrocyanide

The rate constant of a first order reaction are 0.58 S^-1 at 313 K and 0.045 S^-1 at 293 K. What is the energy of activation for the reaction?

Predict the co-ordination No. of cs⁺ ion if `r_(Cs)^+` = 1.69Å and `r_(Cl)^-` = 1.81Å.

IUPAC name of the following compound is

(a) 3 - Bromo- 3, 4- dimethylheptane

(b) 3, 4- dimethyl - 3- bromoheptane

(c) 5- Bromo- 4, 5- dimethylheptane

(d) 4, 5- dimethyl- 5- bromoheptane

Write IUPAC names of the following compounds

Write IUPAC names of the following compounds: