Class 11th

A plot of volume (V) versus temperature (T) for a gas at constant pressure is a straight line passing through the origin. The plots at different values of pressure are shown in Fig. 5.1. Which of the following order of pressure is correct for this gas?

(i) p₁ > p₂ > p₃ > p₄ 

(ii) p₁ = p₂ = p₃ = p₄

(iii) p₁ < p₂ < p₃ < p₄

(iv) p₁ < p₂ = p₃ < p₄

Which of the following property of water can be used to explain the spherical shape of rain droplets?

(i) Viscosity

(ii) Surface tension

(iii) Critical phenomena

(iv) Pressure

Which of the following property of water can be used to explain the spherical shape of rain droplets?

(i) Viscosity

(ii) Ssurface tension

(iii) Critical phenomena

(iv) Pressure

A person living in Shimla observed that cooking food without using pressure cooker takes more time. The reason for this observation is that at high altitude:

(i) Pressure increases

(ii) Temperature decreases

(iii) Pressure decreases

(iv) Temperature increases

4.30. Which hybrid orbitals are used by carbon atoms in the following molecules?

(a) CH₃-CH₃ (b) CH₃-CH=CH₂ (c) CH₃-CH₂-OH (d) CH₃-CHO (e) CH₃COOH.

4.27. Draw diagrams showing the formation of a double bond and a triple bond between carbon atoms in C₂H₄ and C₂H₂ molecules.

4.20 The skeletal structure of CH₃COOH as shown below is correct, but some of the bonds are shown incorrectly. Write the correct Lewis structure for acetic acid.

4.14. Use Lewis symbols to show electron transfer between the following atoms to form cations and anions (a) K and S (b) Ca and O (c) Al and N. 

4.13. Write the resonance structures for SO₃, NO₂ and NO_3.         

3.41. Assertion: The size of an anion will be larger than that of the parent atom.

Reason: The addition of one or more electrons would result in increased repulsion among the electrons and a decrease in effective nuclear charge