<span>a. x and y are atoms of the same element.
If both atoms contain the same amount of protons, they are always the same element.
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ΔH2 = - δH1 δH2 = - 2 x δH1 δH2 = 2 x <span>δ</span>H1
The answer is a identical
The temperature is held constant at (b) and (d). At these points, the substance is changing states. B is changing from solid to liquid and D is changing from liquid to gas
