A gaseous mixture contains O₂ and N₂ in the ratio 1:4 by weight. Then the ratio of their number of molecules in the mixture is

1cc N₂O at STP contains 

A 5 molar solution of H₂SO₄ is diluted from 1 litre to a volume of 10 litres, the normality of the solution will be -

If 0.50 mole of BaCl₂ is mixed with 0.20 mole of Na₃PO₄, the maximum number of moles of Ba₃(PO₄)₂ that can be formed is -

lf equal moles of water and urea are taken in a vessel,The mass percentage of urea in the solution will be -

Sodium bicarbonate on heating decomposes to form sodium carbonate, CO₂ and water. If 0.2 moles of sodium bicarbonate is completely decomposed, how many moles of sodium carbonate is formed?

A purified pepsin was subjected to amino acid analysis. The amino acid present in the smallest amount was lysine, C₆H₁₄N₂O₂ and the amount of lysine was found to be 0.431g per 100 g of protein. The minimum molecular mass of protein is

The number of valence electrons present in 0.53 grams of Na₂CO₃ is

At STP, the density of CCl₄ vapour in g/L will be closest to

If $3.02\times {10}^{19}$ molecules are removed from 98 mg of H₂SO₄, then the number of moles of H₂SO₄ left are -

A chloride of a metal (M) has 65.5% of chlorine. 100 ml of vapour of the chloride of metal at STP weighs 0.72 g. The molecular formula of this metal chloride is

The molality of 0.01 M Na₂CO₃ solution is -

(density of the solution is 1.1 g/ml)

The weight of 1x10²³ molecules of CuSO₄.5H₂O is 

lf N_A is Avogadro's number, then the number of valence electrons in 4.2 g of nitride ions (N${}^{3-}$) will be:

2. 1.01332 x 10⁶ Pa

The SI unit of mass is:

ln the final answer of the expression

$\frac{(29.2-20.2) (1.79\times {10}^5)}{1.37}$

the number of significant figures after solving the expression is:

The volume of carbon dioxide gas evolved at STP by heating 7.3 g of Mg(HCO₃)₂ will be -

The amount of Zinc (atomic weight=65) necessary to produce 224 mL of H₂ by the reaction with dilute suphuric acid will be 

On complete decomposition, the volume of CO₂ released at STP on heating 9.85 g of BaCO₃ (atomic mass, Ba=137) will be 

Specific volume of cylindrical virus particle is $6.02\times {10}^{-2} \mathrm{cc}/\mathrm{g}.$ Whose radius and length are 7 Å and 10 Å respectively. If ${\mathrm{N}}_{\mathrm{A}}=6.02\times {10}^{23},$ the molecular weight of virus is -

 The empirical formula of an oxide of iron, which has 69.9% iron and 30.1% oxygen by mass is -

The mass of sodium acetate (CH₃COONa) required to make 500 mL of 0.375 molars aqueous solution would be -

Molar mass(sodium acetate) = 82.0245 g/mol

The concentration of 69% nitric acid (by mass) in a sample with a density of 1.41 g / mL will be-

The mass of ammonia produced when 2.00 × 10³ g dinitrogen reacts with 1.00 ×10³ g of dihydrogen is 

The total number of electrons present in 1.4 g of dinitrogen gas are -

If ${10}^{10}$ wheat grains are distributed each second, the time taken to distribute one Avogadro number of wheat grains would be -

$$\begin{gathered} 1. 1.91 \times {10}^6 \mathrm{years} \\ 2. 2.31 \times {10}^4 \mathrm{years} \\ 3. 3.84 \times {10}^{6 }\mathrm{years} \\ 4. 1.91 \times {10}^5 \mathrm{years} \end{gathered}$$

A reading on Fahrenheit scale is $200°\mathrm{F}$. The same reading on celsius scale will be :

If 500 mL of a 5 M solution is diluted to 1500 mL, the molarity of the resultant solution is 

The mass per cent of carbon in carbon dioxide is :