Question

Give reasons for each of the following:
a.) A gas exerts pressure on the walls of the containing vessel.
b.) Water is used in cold countries for heating buildings.
c.) Salt is added to remove snow from highways.

Answer 1

a) All the molecules of a gas are in random 3D motion termed Brownian motion in the process of motion they collide with the walls of the container these collisions are elastic and during this collision some pressure is exerted on the walls of the container.

Answer 2

b)water is used to heat as it has a very high specific heat thus in cooling it gives off a large amount of heat.

Answer 3

c) Presence of impurities in ice decreases its melting point so ice melts faster on adding salt.

Answer 4

thanx shankvee

Answer 5

can u explain b) part?

Answer 6

Water's specific heat is very high(4.2kj/kg) that means that if one kg of water cools by 1degree celsius then it will release 4.2kilo joules of energy which is very high so since it releases this much of energy it can easily keep buildings warm.

Answer 7

Why is oxygen called a gas ? Give two reasons.
Shankar B.

Answer 8

it takes the volume of the entire ctanier it is kept in.
It can be compressed very easily to great extents.