Science (English Medium) Class 11 - CBSE Question Bank Solutions

Isotherms of carbon dioxide gas are shown in figure. Mark a path for changing gas into liquid such that only one phase (i.e., either a gas or a liquid) exists at any time during the change. Explain how the temperature, volume and pressure should be changed to carry out the change.

Enthalpy is an extensive property. In general, if enthalpy of an overall reaction A→B along one route is ∆_rH and ∆_rH₁, ∆_rH₂, ∆_rH₃ ..... represent enthalpies of intermediate reactions leading to product B. What will be the relation between ∆_rH for overall reaction and ∆_rH₁, ∆_rH₂ ..... etc. for intermediate reactions.

The difference between C_P and C_V can be derived using the empirical relation H = U + pV. Calculate the difference between C_P and C_V for 10 moles of an ideal gas.

The enthalpy of vapourisation of \[\ce{CCl4}\] is 30.5 kJ mol^–1. Calculate the heat required for the vapourisation of 284 g of \[\ce{CCl4}\] at constant pressure. (Molar mass of \[\ce{CCl4}\] = 154 g mol^–1).

Draw the gas phase and solid phase structure of \[\ce{H2O2}\].

Write the Lewis structure of hydrogen peroxide.

How will you concentrate \[\ce{H2O2}\]? Show differences between structures of \[\ce{H2O2}\] and \[\ce{H2O}\] by drawing their spatial structures. Also mention three important uses of \[\ce{H2O2}\].

A colourless liquid ‘A’ contains H and O elements only. It decomposes slowly on exposure to light. It is stabilised by mixing urea to store in the presence of light. Suggest possible structure of A.

An alkane C₈H₁₈ is obtained as the only product on subjecting a primary alkyl halide to Wurtz reaction. On monobromination this alkane yields a single isomer of a tertiary bromide. Write the structure of alkane and the tertiary bromide.

Use Bohr's postulate to prove that the radius of n^th orbit in a hydrogen atom is proportional to n².

The increasing order of reactivity among group 1 elements is Li < Na < K < Rb <Cs whereas that among group 17 elements is F > CI > Br > I. Explain.

The first (Δ₁H₁) and the second (Δ₁H₂) ionization enthalpies (in kJ mol^-1) and the (Δ_egH) electron gain enthalpy (in kJ mol^-1) of a few elements are given below:

Which of the above elements is likely to be the least reactive element.

The first (Δ₁H₁) and the second (Δ₁H₂) ionization enthalpies (in kJ mol^-1) and the (Δ_egH) electron gain enthalpy (in kJ mol^-1) of a few elements are given below:

Which of the above elements is likely to be the most reactive metal.

The first (Δ₁H₁) and the second (Δ₁H₂) ionization enthalpies (in kJ mol^-1) and the (Δ_egH) electron gain enthalpy (in kJ mol^-1) of a few elements are given below:

Which of the above elements is likely to be the most reactive non-metal.

The first (Δ₁H₁) and the second (Δ₁H₂) ionization enthalpies (in kJ mol^-1) and the (Δ_egH) electron gain enthalpy (in kJ mol^-1) of a few elements are given below:

Which of the above elements is likely to be the least reactive non-metal.

The first (Δ₁H₁) and the second (Δ₁H₂) ionization enthalpies (in kJ mol^-1) and the (Δ_egH) electron gain enthalpy (in kJ mol^-1) of a few elements are given below:

Which of the above elements is likely to be the metal which can form a stable binary halide of the formula MX₂, (X=halogen).

The first (Δ₁H₁) and the second (Δ₁H₂) ionization enthalpies (in kJ mol^-1) and the (Δ_egH) electron gain enthalpy (in kJ mol^-1) of a few elements are given below:

Which of the above elements is likely to bethe metal which can form a predominantly stable covalent halide of the formula MX (X = halogen)? 

Considering the elements F, Cl, O and N, the correct order of their chemical reactivity in terms of oxidizing property is ______.

Calculate the wavelength of an electron moving with a velocity of 2.05 × 10⁷ ms^-1.

The mass of an electron is 9.1 × 10^–31 kg. If its K.E. is 3.0 × 10^–25 J, calculate its wavelength.