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प्रश्न
Mention the contribution of the following scientists :
- Antoine Lavoisier
- Robert Boyle
- Joseph Priestley
- Sir W. Ramsay
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उत्तर
- 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.
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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` |
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