271.

The number of atoms in 0.1 moles of a triatomic gas is (N_A = 6.02 x 10²³ mol^-1)

• 6.026 x 10²²

• 1.806 x 10²³

• 3.600 x 10²³

• 3.600 x 10²³

10 g of hydrogen and 64 of oxygen were filled in a steel vessel and exploded. Amount of water produced in this reaction will be

• 2 mol

• 3 mol

• 4 mol

• 4 mol

Number of moles of MnO₄^- required to oxidies one mole of ferrous oxalate completely in acidic medium will be 

• 0.6 mole

• 0.4 mole

• 7.5 mole

• 7.5 mole

An Organic compound contains carbon, hydrogen and oxygen. Its elemental analysis gave C, 38.71% and H, 9.67%. The empirical formula of the compound would be

• CH₃O

• CH₂O

• CHO

• CHO

How many moles of lead (II) chloride will be formed from a reaction between 6.5 g of PbO and 3.2 g of HCl?

• 0.044

• 0.333

• 0.011

• 0.011

An element, X has the following isotopic composition;


²⁰⁰X: 90%

¹⁹⁹X : 8.0%

²⁰²X ; 2.0 %

The weighted average atomic mass of the naturally -occurring element X is closet to:

• 200 amu

• 201 amu

• 202 amu

• 202 amu

Work is being performed, when a weight lifter lifts a base ball off a weight rack. This is due to

• magnetic attraction

• gravity

• electrostatic repulsion

• mechanical force

11.2 L of gas at STP Weight 14g. The gas would be

• H₂

• CO

• B₂H₆

• All of these

For preparing 3.00 L of 1M NaOH by mixing portions of two stock solutions (A and B) of 2.50 M NaOH and 0.40 M NaOH respectively. Find out the amount of B stock solution (in L) added.

• 8.57 L

• 2.14 L

• 1.28 L

• 7.51 L

What would be the heat released when an aqueous solution containing 0.5 mole of HNO₃ is mixed with 0.3 mole of OH^-?  (enthalpy of neutralisation is- 57.1 kJ)

• 28.5 kJ

• 17.1 kJ

• 45.7 kJ

• 1.7 kJ