Astudent has a thin copper beaker containing 100g of a pure metal in the solid state. the metal is at 215 degrees celsius, its exact melting temperature. if the student lights a bunsen burner and holds it for a fraction of a second under the beaker, what will happen to the metal? mcat

A small amount of the solid metal in the beaker will melt and the temperature would remain unchanged (melting point).

Explanation:

The melting point of the metal is 215 C. Given that the copper beaker with solid metal is maintained at its melting point. At this temperature, the latent heat of fusion of the solid is overcome and the solid starts to melt to the liquid state. When the copper beaker with the metal is placed on a Bunsen burner for a fraction of seconds, a small amount of the solid metal would melt but the temperature would still remain the same. This is because the small amount of heat generated by the burner will not be sufficient for the melting of 100 g of the solid. Therefore, only a small amount of the solid metal would melt keeping the temperature constant as the extra heat from burner would be used in the process of phase change from solid to liquid.

Given that the bunsen burner heats up at least 215 degrees C, then beaker will melt during that fraction of a second and will then cool down at a temperature lesser than 215 degrees. This is due to the surrounding atmosphere of the beaker, after the beaker reaches or exceeds its melting point, the beaker will melt but then after some time, its temperature will cool down.

Bases are the hydroxides of the alkali and alkaline earth metals (sodium, calcium, etc.) and the water solutions of ammonia or its organic derivatives (amines). Such substances produce hydroxide ions (OH-) in water solutions.