Glass panes usually appear hazy because:
Water vapour settling on the tiny dust particles
Of chemical reactions
It is property of all transparent substances
They are old
Smoke is an example of:
Liquid-in-gas mixture
Gas-in-solid mixture
Solid-in-gas mixture
Gas-in-liquid mixture
Which of the following is combustible ?
Oxygen
Carbon dioxide
Hydrogen
All
Which of the following can show the direction of wind?
Anemometer
Wind vane
Wind mill
Barometer
The correct ascending order of gases as per their composition in air is:
Oxygen < carbon dioxide < nitrogen
Hydrogen < oxygen < nitrogen
Nitrogen < hydrogen < oxygen
Oxygen < Carbon dioxide < hydrogen
Which of the following statement is true regarding earth's atmosphere?
It gets denser with increase in altitude
It gets thinner with increase in altitude
Its thickness is atleast one fourth the radius of the earth
It contains no solid particles
We can find tiny droplets of water on the outer surface of a steel glass containing cold water or ice. This shows that:
Steel contains air
Air contains water vapour
Cold water can seep through solids
None of these
Mountaineers carry oxygen cylinders with them because:
Oxygen supports combustion
Air becomes thinner as we go higher
Air is dense but lacks oxygen in mountains
When we heat water, we can find bubbles coming from it. This shows that:
Water contains air
Air contains water
Hot water becomes bubbles
Lime water turns milky when exposed to air and stirred. This shows that air contains:
Nitrogen