The amount of BaSO₄ precipitated on mixing BaCl₂ (0.5 M) with H₂SO₄ (1 M) will correspond to

• 0.5 M

• 1.0 M

• 1.5 M

• 2.0 M

One mole of SO₃ was placed in a vessel of 1 L capacity at a certain temperature and the following equilibrium was established.

2SO₃ (g) $\rightleftharpoons$ 2SO₂ (g) + O₂ (g)

If 0.6 moles of SO₂ were formed at equilibrium, K_c for the reaction will be

• 0.036

• 0.45

• 0.54

• 0.675

$\mathrm{\alpha }$-particles can be detected by using

• thin aluminium sheet

• barium sulphate

• zinc sulphide screen

• gold foil

The pair of amphoteric hydroxides is

• Be(OH)₂, Al(OH)₃

• Al(OH)₃, LiOH

• B(OH)₃, Be(OH)₂

• Be(OH)₂, Mg(OH)₂

For the reaction of one mole of zinc dust with one mole of sulphuric acid in a bomb calorimeter, $∆$U and w correspond to

• $∆$U < 0, w = 0

• $∆$U < 0, w < 0

• $∆$U > 0, w = 0

• $∆$U > 0, w > 0

In a decay process ${}_{\mathrm{Z}}{}^{\mathrm{A}}\mathrm{X}$ changes into ${}_{\mathrm{Z}-1}{}^{\mathrm{A}}\mathrm{Y}$. Which process is this?

• $\mathrm{\beta }$-decay

• ${\mathrm{\beta }}^{+}$ decay

• $\mathrm{\alpha }$- decay

• $\mathrm{\gamma }$- decay.

7.

Which of the following arrangement is possible?

• n	l	m	s
  5	2	2	+1/2

• 2

  2

  0

  -1/2

• 3

  -2

  1

  +1/2

• 0

  0

  1

  +1/2

How many significant figures are present in 0.0000135?

• 7

• 8

• 4

• 3

Assertion : Molecular nitrogen is less reactive than molecular oxygen.

Reason: The bond length of N₂ is shorter than that of oxygen.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : NF₃ is a weaker ligand than N(CH₃)₃.

Reason : NF₃ ionizes to give F^- ions in aqueous solution.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.