English CA 6

One of the following is a mixture

• sand

• urea

• brass

• sucrose

What are the possible oxidation numbers for an element if its atomic number is 17?

• -1 and 7

• -1 and 6

• -3 and 5

• -2 and 6

In which of the following is the oxidation state of oxygen different from its value in water?

• OH–

• H³O+

• H²O²

• SO²

How much of magnesium is required with 250cm³ of 0.5M HCl? [ Mg = 24]

• 0.3g

• 1.5g

• 2.4g

• 3.0g

The mass of copper deposited when a current of 2.0A is passed through a solution of a copper salt for 60 minutes is [Cu= 64, 1F = 96500C/mol]

• 4.7g

• 0.04g

• 2.39g

• 9.55g

When a few drops of water are added to a blue anhydrous cobalt (II) chloride, the colour change to

• White

• Pink

• Red

• Blue

The weakest attractive forces that can be observed between two molecules is

• ionic

• covalent

• coordinate covalent

• Van der waals

An oxide XO² has a vapour density of 32. What is the atomic mass of X ?

• 32

• 20

• 14

• 12

Which of the following substances is not a salt?

• Zinc Chloride

• Aluminum Oxide

• Sodium hydrogentetraoxosulphate(VI)

• Magnesium Iodide

Which of the following cannot replace hydrogen from water or steam?

• Copper

• Iron

• Magnesium

• Calcium