Energy in the form of heat is wasted when a machine is operated. This heat is generated due to ___________.
burning
friction
combustion
lubrication
Acetic Acid is another name for which of the following?
Vinegar
Baking Soda
Copper Sulphate
Magnesium Oxide
The process of depositing a layer of any desired metal on another metal by means of electricity is called ...........
Electroplating
Galvanisation
Rusting
Crystallisation
The salt concentration (measured as salinity in parts per thousand), is..........% in sea.
10-20
30-35
40-50
60-70
B.
30-35
A change in which one or more new substances are formed is called .................
Physical Change
Chemical Change
Rusting
Galvanisation
The property of metals by which they can be beaten into thin sheets is called ................
ductility
malleability
viscosity
tensile strength
The salt concentration (measured as salinity in parts per thousand), is greater than .............% in hypersaline lagoons.
50
100
150
200
The temperature at which a solid melts to become a liquid at atmospheric pressure is called..........
crystallisation
melting point
evaporation
galvanisation