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How does a mirage trick the eye?

A mirage is a kind of optical illusion that occurs in hot, still weather. A pool of water suddenly appears in the distance. But on approaching, it seems to evaporate and there’s actually no water at all. You may see these mirages on roads in summer. They also occur in deserts, sometimes complete with trees, and may trick a thirsty …

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How do you test the presence of methanol?

Methanol does not respond to the iodoform test. In fact, the test is given by ethanol and those alcohols which possess -hydroxymethyl group or -CH(OH)- group or carbonyl compounds having acetyl functionality. Methanol can be detected by the oil of wintergreen test. In this test, 1-2 ml of methanol along with few crystals of salicylic acid are treated with concentrated …

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How do we catch a cold?

Despite much research, nobody is completely certain why some people catch colds while others do not. Cold research clinics take volunteers in the hope of finding the cause and cure of the common cold but the strange thing is that while some of the volunteers do catch cold, others simply do not become infected. Their natural resistance to the cold …

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