Popular belief contends that water freezes at 32 degrees Fahrenheit (0 degrees Celsius). Surprisingly, if water lies in a smooth bottle and is free of any dust, it can stay liquid down to minus 40 degrees F (minus 40 degrees C) in what's called "supercooled" form. The dust and rough surfaces that water is normally found in contact with in nature can serve as the kernels around which ice crystals form.
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That sounds strange