Forum

Chemical Equilibrium – Le Chatelier’s Principle

For the reaction N2(g) + 3H2(g) ⇌ 2NH3(g), predict how the equilibrium position will shift with (i) an increase in pressure, (ii) a decrease in temperature, and (iii) an addition of a catalyst.

01/11/2024

Chemistry

12th (Science)

Surface Chemistry – Catalysts and Enzymes

Define catalyst and enzyme. Describe two differences between homogeneous and heterogeneous catalysis, giving examples for each

01/11/2024

Chemistry

12th (Science)

Thermodynamics – Entropy Change

Explain the concept of entropy. Calculate the change in entropy when 2 moles of an ideal gas expand isothermally and reversibly from a volume of 5 liters to 15 liters at 300 K.

01/11/2024

Chemistry

12th (Science)

Organic Chemistry – Functional Group Identification

Identify the functional groups in the following compounds and provide their IUPAC names: (i) CH3CH2OH (ii) CH3COCH3 (iii) CH3COOH.

01/11/2024

Chemistry

12th (Science)

Integers

The value of 5 ÷ (–1) does not lie between
(a) 0 and – 10 (b) 0 and 10 (c) – 4 and – 15 (d) – 6 and 6

01/11/2024

Mathematics

7th

Integers

On the number line, the value of (–3) × 3 lies on right hand side of
(a) – 10 (b) – 4 (c) 0 (d) 9

01/11/2024

Mathematics

7th

Integers

Which of the following statements is not true?
(a) When two positive integers are added, we always get a positive integer.
(b) When two negative integers are added we always get a negative integer.
(c) When a positive integer and a negative integer is added we always get a negative integer.
(d) Additive inverse of an integer 2 is (– 2) and additive inverse of ( – 2) is 2.

01/11/2024

Mathematics

7th

Integers

The next number in the pattern – 62, – 37, – 12 _________ is
(a) 25 (b) 13 (c) 0 (d) –13

01/11/2024

Mathematics

7th

Integers

Next three consecutive numbers in the pattern 11, 8, 5, 2, –, –, –are
(a) 0, – 3, – 6 (b) – 1, – 5, – 8 (c) – 2, – 5, – 8 (d) – 1, – 4, – 7

01/11/2024

Mathematics

7th

Electrostatics – Potential Energy of a System of Charges

Three point charges, each of +2 μC, are placed at the vertices of an equilateral triangle with sides of length 0.3 meters. Calculate the total electrostatic potential energy of the system.

01/11/2024

Physics

12th (Science)