Answers

2015-07-01T16:41:40+05:30
No, the mass does not change instead the volume i.e., the space occupied by the substance after undergoing change of its state. For example, when we take 1 kg of water, and ten freeze it measure its weight , we find that the weight remains constant but the amount of space occupied by the ice has been changed.
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2015-07-01T19:48:38+05:30
The guy above has answered much but he did not mention that all matter follow the Law of Conservation of Mass
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