11.

The number of α and β- particles emitted during the transformation of ₉₀Th²³² to ₈₂Pb²⁰⁸ respectively are

• 4, 2

• 2, 2

• 8, 6

• 6, 4

In a lime kiln to get higher yield of CO₂, the measure that can be taken is

• to remove

• to add more CaCO₃

• to mamtain high temperature

• to pump out CO₂

What is the volume of "20 volume H₂O₂" required to get 5000 cm³ of oxygen at STP?

• 250 cm³

• 50 cm³

• 100 cm³

• 125 cm³

Two gas cylinders having same capacity have been filled with 44 g of H₂ and 44 g of CO₂ respectively. If the pressure in CO₂ cylinder is 1 atmosphere at a particular temperature, the pressure in the hydrogen cylinder at the same temperature is 

• 2 atmosphere

• 1 atmosphere

• 22 atmosphere

• 44 atmosphere

Angular momentum ofan electron in the n^th orbit of hydrogen atom is given by

• $\frac{\mathrm{nh}}{2\mathrm{\pi }}$

• nh

• $\frac{2\mathrm{\pi }}{\mathrm{nh}}$

• $\frac{\mathrm{\pi }}{2\mathrm{nh}}$

The element with atomic number 36 belongs to ........ block in the periodic table.

• p

• s

• f

• d

Kinetic energy of one mole of an ideal gas at 300 Kin kJ is

• 3.74

• 348

• 34.8

• 3.48

A gaseous carbon compound is soluble in dilute HCl. The solution on treating with NaNO₂ gives off nitrogen leaving behind a solution which smells of wood spirit. The carbon compound is

• HCHO

• CO

• C₂H₅NH₂

• CH₃NH₂

A galvanic cell is constructed using the redox reaction,

$\frac{1}{2}{\mathrm{H}}_2 \left(\mathrm{g}\right) + \mathrm{AgCl} \left(\mathrm{s}\right) \rightleftharpoons {\mathrm{H}}^{+} \left(\mathrm{aq}\right) + {\mathrm{Cl}}^{-} \left(\mathrm{aq}\right) + \mathrm{Ag}$

it is represented as

• Pt | H₂ (g) | HCl (sol)|| AgNO₃ (sol) | Ag

• Ag | AgCl (s) | KCl (sol) || HCl (sol), H₂ (g) | Pt

• Pt | H₂ (g) | KCl (sol) || AgCl (s) | Ag

• Pt | H₂ (g), HCl (sol) || AgCl (s) | Ag

A signature, written in carbon pencil weighs 1 mg. What are the number of carbon atoms mpresent in the signature?

• 5.02 × 10²³

• 5.02 × 10²⁰

• 6.02 × 10²⁰

• 0.502 × 10²⁰