Students find that water can be created in a lab by burning hydrogen gas in air. They conclude that water is not a compound because only hydrogen is used to form the water. What is wrong with their conclusion?

Explanation:

Their conclusion is wrong because air is a mixture of many gases. The gas that combines with hydrogen to form the water is oxygen gas.

Hydrogen gas combines with oxygen gas to form water.

Water is made up of the elements hydrogen and oxygen.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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