Among the elements Ca, Mg, P and Cl, the order of increasing atomic radii is

• Mg< Ca< Cl< P

• Cl <P <Mg< Ca

• P <Cl< Ca< Mg

• Ca <Mg <P < Cl

The reaction

           2A(g) + B(g) $\rightleftharpoons$3C(g) + D(g)

is begun with the concentrations of A and B both at an initial value of 1.00 M. When equilibrium is reached, the concentration of D is measured and found to be 0.25 M. The value for the equilibrium constant for this reaction is given by the expression

• [(0.75)³ (0.25)] $÷$ [(1.00)² (1.00)]

• [(0.75)³ (0.25)] $÷$ [(0.50)² (0.75)]

• [(0.75)³ (0.25)] $÷$ [(0.50)² (0.25)]

• [(0.75)³ (0.25)] $÷$ [(0.75)² (0.25)]

The pressure exerted by 6.0g of methane gas in a 0.03 m³ vessel at 129°C is (Atomic masses: C = 12.01, H = 1.01 and R= 8.314JK^-1 mol^-1)

• 215216 Pa

• 13409 Pa

• 41648 Pa

• 31684 Pa

Match List I (Equations) with List II (Types of process) and select the correct option.

• A	B	C	D
  1	2	3	4

• A	B	C	D
  3	4	2	1

• A	B	C	D
  4	1	2	3

• A	B	C	D
  2	1	1	3

Among the following which one has the highest cation of anion size ratio?

• Csl

• CsF

• LiF

• NaF

Some of the properties of the two species, ${\mathrm{NO}}_3^{-} \mathrm{and} {\mathrm{H}}_3{\mathrm{O}}^{+}$ are described below. Which one of them is correct?

• Dissimilar in hybridisation for the central atom with different structures

• Isostructural with same hybridisation for the central atom

• Isostructural with different hybridisation for the central atom

• Similar in hybridisation for the central atom with different structures

Which has the maximum number of molecules among the following?

• 44 g CO₂

• 48 g O₃

• 8g H₂

• 64g SO₂

Consider the following processes $∆\mathrm{H} (\mathrm{kJ}/\mathrm{mol})$

      $$\begin{gathered} \frac{1}{2}\mathrm{A} \to \mathrm{B} + 150 \\ 3\mathrm{B} \to 2\mathrm{C} + \mathrm{D} - 125 \\ \mathrm{E}+\mathrm{A} \to 2\mathrm{D} + 350 \\ \mathrm{for} \mathrm{B}+ \mathrm{D} \to \mathrm{E} + 2\mathrm{C}, ∆\mathrm{H} \mathrm{will} \mathrm{be} \end{gathered}$$

• 525 k.J/mol

• -175 kJ/mol

• -325kJ/mol

• 325 kJ/mol

Which of the following structures is the most preferred and hence of lowest energy for SO₃?

What is the value of electron gain enthalpy of Na if IE₁ of Na = 5.1 eV?

• -5.1 eV

• -10.2 eV

• +2.55 eV

• +10.2eV