# Is there a way to find specific heat (c) without knowing Delta T?

t-nez | High School Teacher | (Level 3) Associate Educator

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Specific heat of a substance is the amount of heat required to raise the temperature of one gram of the substance by one degree Celsius. It is a common physical property of a substance and specific heats for many substances are found in tables of thermodynamic data in chemistry textbooks and on websites.

If you're trying to calculate the specific heat for an unknown substance then you'll need to measure the change in temperature of the substance, or delta T, when it gains or loses heat. This is sometimes done to compare the calculated specific heat to values of known substances for the purpose of identifying the unknown.

One way to do this is to immerse the sample in boiling water and allow it to come to the same temperature, 100 degrees C. Then, quickly immerse the sample in a known mass of water at a known temperature. The heat lost by the sample will equal the heat gained by the water, which is:

q = mc `Delta` T

where m is the mass of water, c is the specific heat of water and  `Delta` T is the temperature change of the water. You can then find c for the unknown sample  using the same equation, as you know the heat gained and the temperature change of the unknown. ` <br> `