Which of the following does not cause a depletion in the water table of a place?
Constructing factories and houses
Making concrete roads and floors
Deforestation
All of these
Metals react with water to form:
oxides and hydroxides
oxides and chlorides
hydroxides and carbonates
oxides and sulphides
Specific heat of water is:
very high
very low
medium
sometimes high and sometimes low
Impurities in water:
Lower the freezing point
increase the boiling point
none of these
both of these
When water is cooled it contracts until it reaches ______ and then it starts expanding.
37oC
40oC
0oC
4oC
The percentage of water in human body is:
80%
70%
60%
50%
The density of water is greatest at:
100oC
Water produces hydrogen and oxygen in the ratio of:
1 : 1
2 : 1
1 : 2
2 : 3
Which of the following is mostly used as a drinking water source by us?
Sea water
Glaciers
Ground water
Brackish water
The density of water is:
0.5 g/cm3
0.1 g/cm3
10 g/cm3
1 g/cm3
