Figure GT.7

States of matter. Mount Robson (elevation 3,954 m or 12,972 ft), in British Columbia, is the highest peak in the Canadian Rockies. Berg Glacier flows down the mountain and into Berg Lake. Here, water exists in its three phases: solid ice in Berg Glacier, liquid water in Berg Lake, and water vapor (a gas) that is invisible in the atmosphere. To change the state of water from solid ice to liquid water to water vapor, energy must be added to the water. To change its state from gas to liquid to solid, energy must be removed from water.

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