20 mL solution of 0.1 M ferrous sulphate was completely oxidised using a suitable oxidising agent. What is the number of electrons exchanged?

• 1.204 x 10²²

• 193

• 1930

• 1.204 x 10²¹

The molecular formula of a commercial resin used for exchanging ions in water softening is C₈H₇SO₃Na ( mol. wt = 206). What would be the maximum uptake of Ca²⁺ ions by the resin when expressed in mole per gram resin?

• 1/103

• 1/206

• 2/309

• 2/309

In Carius method of estimation of halogens, 250 mg of an organic compound gave 141 mg of AgBr. The percentage of bromine in the compound is: (at. Mass Ag = 108; Br = 80)

• 24

• 36

• 48

• 48

A gaseous hydrocarbon gives upon combustion 0.72 g of water and 3.08 g of CO₂.The empirical formula of the hydrocarbon is 

• C₂H₄

• C₃H₄

• C₆H₅

• C₆H₅

Experimentally it was found that a metal oxide has formula M_0.98O. Metal M, is present as M²⁺ and M³⁺ in its oxide. The fraction of the metal which exists as M³⁺ would be:

• 7.01%

• 4.08%

• 6.05%

• 6.05%

The most abundant element by mass in the body of a healthy human adult are :
Oxygen (61.4%) ; Carbon (22.9%), Hydrogen(10.0%) ; and Nitrogen (2.6%). The weight which a 75 kg person would gain if all 1H atoms are replaced by 2H atoms is

• 15 kg

• 37.5 Kg

• 7.5 Kg

• 7.5 Kg

7.

How many moles of magnesium phosphate, Mg₃(PO₄)² will contain 0.25 mole of oxygen atoms?

• 0.02

• 3.125 × 10^–2

• 1.25 × 10^–2

• 1.25 × 10^–2

If we consider that 1/6 in place of 1/12 mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of a substance will 

• Decrease twice

• Increase two fold

• Remain unchanged

• Remain unchanged

The ratio of mass percent of C and H of an organic compound (C_XH_YO_Z) is 6: 1. If one molecule of the above compound (C_XH_YO_Z) contains half as much oxygen as required to burn one molecule of compound C_XH_Y completely to CO₂ and H₂O. The empirical formula of compound C_XH_YO_Z is

• C₂H₄O₃

• C₃H₆O₃

• C₂H₄O

• C₃H₄O₂

0.126 g of an acid is needed to completely neutralise 20 mL 0.1 (N) NaOH solution. The equivalent weight of the acid is

• 53

• 40

• 45

• 63