Advertisements
Advertisements
Question
Mention the contribution of the following scientists :
- Antoine Lavoisier
- Robert Boyle
- Joseph Priestley
- Sir W. Ramsay
Advertisements
Solution
- Antoine Lavoisier
Conducted experiments to know the nature of combustion. - Robert Boyle
Discovered a rule about how gases behave - Joseph Priestley
Prepared oxygen by heating red mercuric oxide with infra red rays from Sun and proved that air was not an element. - Sir W. Ramsay
Sir William Ramsay, alongwith Lord Raleigh discovered ar-gon; a noble gas, which is also called as rare gas or inert gas. He also prepared neon, krypton and xenon by distillation of liquid air. In 1910, he discovered radon.
APPEARS IN
RELATED QUESTIONS
Match the statements in Column A, with those in Column B.
| Column A | Column B |
| 1. Largest Constituent of air, which dilutes the activity of oxygen. | (a) Oxygen |
| 2. A gas used for filling weather observeation balloons. | (b) Carbonic acid |
| 3. An acid formed by the dissolution of sulphur dioxide gas in water. | (c) Sulphuric acid |
| 4. An acid formed by the dissolution of carbon dioxide in water. | (d) Helium |
| 5. A gas vital for respiration. | (e) Nitrogen |
Discuss harmful effects of greenhouse effect.
What do you observe when a burning candle is covered with an inverted jar.
State two similarities and two differences between respiration and burning.
How is air useful to agriculture?
Write ‘true’ or ‘false for the following;
Air is a compound.
Tick (√) the correct alternative from the choice given for the following statement.
Which of the following is not a greenhouse gas?
Take a squeezable bottle. Make a hole on the lid and close the bottle tightly. Bring the bottle near your face and press the bottle. What do you feel?
The composition of air is always exactly the same.
In the boxes of Column, I the letters of some words got jumbled. Arrange them in proper form in the boxes given in Column II
| Column I | Column II | ||
| (a) | \[\boxed{\text{D}}\]\[\boxed{\text{I}}\]\[\boxed{\text{L}}\]\[\boxed{\text{L}}\]\[\boxed{\text{M}}\]\[\boxed{\text{W}}\]\[\boxed{\text{I}}\]\[\boxed{\text{N}}\] | (a) | `squaresquaresquaresquaresquaresquaresquare square` |
| (b) | \[\boxed{\text{Y}}\]\[\boxed{\text{N}}\]\[\boxed{\text{O}}\]\[\boxed{\text{G}}\]\[\boxed{\text{X}}\]\[\boxed{\text{E}}\] | (b) | `squaresquaresquaresquaresquare square` |
| (c) | \[\boxed{\text{M}}\]\[\boxed{\text{E}}\]\[\boxed{\text{S}}\]\[\boxed{\text{K}}\]\[\boxed{\text{O}}\] | (c) | `squaresquaresquaresquaresquare` |
| (d) | \[\boxed{\text{T}}\]\[\boxed{\text{U}}\]\[\boxed{\text{D}}\]\[\boxed{\text{S}}\] | (d) | `squaresquaresquare` |
