What is the mass of hydrogen peroxide present in 1 litre of 2M solution? Calculate the volume of oxygen at STP liberated upon the complete decomposition of 100 cm³ of the above solution.

Is demineralised or distilled water useful for drinking purposes? If not, how can it be made useful?

How does H₂O₂ behave as a bleaching agent?

Which one of the following statements about water is false?

• Water can act both as an acid and as a base.

• There is extensive intramolecular hydrogen bonding in the condensed phase.

• Ice formed by heavy water sinks in normal water.

• Ice formed by heavy water sinks in normal water.

The concentration of fluoride, lead, nitrate and iron in a water sample from an underground lake was found to be 1000 ppb, 40 ppb, 100 ppm and 0.2 ppm, respectively. This water is unsuitable for drinking due to the high concentration of:

• Lead

• Nitrate

• Iron

• Iron

168.

From the following statements regarding H₂O₂, choose the incorrect statement:

• It can act only as an oxidising agent

• It decomposed on exposure to light

• It has to be stored in plastic or wax lined glass bottles in dark

• It has to be stored in plastic or wax lined glass bottles in dark

In which of the following reactions H₂O₂ acts as a reducing agent?
I. H₂O₂ + 2H⁺ + 2e^- →2H₂O
II. H₂O₂ - 2e^- →O₂ + 2H⁺
III. H₂O₂ +2e^-→ 2OH^-
IV. H₂O₂+ 2OH^- -2e^- →O₂ + 2H₂O

• I and II

• III and IV

• I and III

• I and III

Very pure hydrogen (99.9%) can be made by which of the following processes?

• Reaction of methane with steam

• Mixing natural hydrocarbons of high molecular weight

• Electrolysis of water

• Electrolysis of water