Chemistry Question Bank

The mixture of concentrated HCl and HNO3 made in 3 : 1 ratio contains (AIIMS 2013)

Which of the following is not a peroxyl acid? (Manipal 2012)

When a colorless gas is passed through bromine water, only decolourisation takes places. The gas is (AFMC 2012)

When Cl2 gas reacts with hot and concentrated sodium hydroxide solution, the oxidation number of chlorine changes from (CBSE AIPMT 2012) (a)zero to +1 and zero to –5

Which one of the following statements is not valid for oxoacids of phosphorous? (Manipal 2012)

When conc. H2SO4 is heated with P2O5 the acid is converted to (UP CPMT 2012)

Which of the following statements is correct for the iodine molecule?

All the halogens are coloured. The colours arise due to

Which one among the following is the most powerful oxidizing agent?

Which of the following halogens has only one oxidation state of –1 in an aqueous solution?

Which of the following elements can have both positive and negative oxidation states?

A gas that cannot be collected over water is

In the cyclo-S8 molecule of rhombic sulphur, all the S—S bond lengths and all the S—S—S bond angles are respectively (approximate values)

Which of the following is/are correct?

O3 cannot oxidise:

A green coloured solution of a salt changes its colour to light pink on passing ozone through it. Which of the following species represent pink and green colour respectively ?

In the presence of water, sulphur is oxidized by ozone to give

The gases absorbed by alkaline pyrogallol and oil of cinnamon are respectively

At room temperature, O3 is absorbed by

Ozone is an extremely powerful oxidizing agent. It is

Which of the following statements is correct?

Ozonized oxygen is a mixture of

Ozone is prepared by the action of silent electric discharge upon oxygen in an apparatus called ozonizer. The reaction

The number of P—O—P bonds in cyclic metaphosphoric acid is

The number of P–O–P bonds in the structure of phosphorus pentoxide and phosphorus trioxide are respectively (2005)