3. Elements, Compounds and Mixtures (Experimental Techniques)
Click the correct answer (True or False).
Krypton and radon are non-metals and are reluctant to react chemically with other elements or compounds.
True
False
A molecule of ammonia gas is represented as NH2.
True
False
A mixture does not have definite physical and chemical properties.
True
False
Air is a gas-gas homogeneous mixture.
True
False
In the process of sublimation, to separate a mixture of common salt and ammonium chloride, common salt sublimes on heating whereas ammonium chloride does not.
True
False
2H2O contains four atoms of hydrogen and two atoms of oxygen.
True
False
Steel, bronze and brass are alloys.
True
False
An emulsion is a mixture in which atoms of one liquid are dispersed in another liquid.
True
False
A suspension is a heterogeneous mixture that consists of small solid particles suspended in a liquid.
True
False
Click the correct answer.
Which of the following metals are found in liquid state?
Gallium, mercury
Sodium, potassium
Gallium, sodium
Mercury, potassium
Which group of the given metals has low melting and boiling points?
Potassium, zinc, sodium
Potassium, calcium, sodium
Mercury, calcium, sodium
Potassium, calcium, gallium
Which of the following non-metals have luster?
Bromine, iodine
Iodine, carbon
Carbon, graphite
Iodine, graphite
Graphite is form of which of the following?
Carbon
Pure element
Metal
Metalloid
Symbols are usually short forms or abbreviated names of which of the following?
Atoms
Elements
Molecules
Compounds
How many atoms are there in 2 molecules of phosphorus?
1
2
4
8
Which of the following is the chemical formula of sulphur trioxide?
SO3
SO
SO2
SO4
FeS is the chemical formula of which of the following?
Iron sulphate
Iron (II) sulphide
Iron (II) sulphite
Iron (III) sulphide
Which type of water is used by doctors, chemists and pharmaceutical companies?
Tap
Filter
Cold
Distilled
Click each box on the left and then click the matching box on the right.
