1.
Handpicking is used to separate slightly large sized impurities. It is used when the quantity of impurities is not very large.
2.
Foe larger quantities, threshing is done in the traditional way; by using animals. For this, stalks are spread around a pole. Several bullocks are tied to the pole and are made to walk over the harvested stalks.
3.
The process of conversation of water vapour into its liquid form is called condensation.
4.
No
5.
When the quantity is small, threshing is done manually. Small bundles of the harvested stalks are thrashed on a hard surface. This helps in separating the grains.
6.
Combine Harvester means farming is done by use of the machine. This machine harvests threshes and winnows in a single operation.
7.
A solution is prepared by dissolving a substance in a liquid.
8.
When steam comes in contact with the metal plate cooled with ice, it condenses and forms liquid water.
9.
Salt is prepared from sea water by evaporation and condensation. Seawater is collected in shallow pits and allowed to evaporate. The water evaporates and crystals of salt are obtained in the pits. The salt is then sent to factories for further purification
10.
machine
11.
When more solid can be dissolved in the given solution is called unsaturated solution.
12.
evaporation, condensation.
13.
The USA, India (Punjab)
14.
Winnowing
15.
Threshing machines are used to remove the grains and seeds from stalks and husks. It can be powered by either a diesel engine or an electric motor. It helps on saving time and labour.
16.
Yes. There are two reasons: 1. To separate two different but useful components.; 2. To remove impurities or non-useful component from a mixture.
17.
threshing
18.
threshing
19.
When no more solute can be dissolved in the amount of solvent taken, the solution is said to be saturated solution.
20.
sedimentation