i am trying to solve a specific heat equation and i cant figure out which variables go with which givens? or what im trying to solve for.

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steveschoen | College Teacher | (Level 1) Associate Educator

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The specific heat equation is Q = m*c*`Delta`T

Q = heat

m = mass

c = specific heat

`Delta` T = change in temperature

From a message, we are given:

"suppose you have a 2.000 lb block of iron at 50.0°C. How much heat in Joules would it take to warm this block to 75.0°C?"  So the mass is 2.000 lbs, the change in temp is 25.0°C but I don't understand what the heat and specific heat are?

So, we are looking for Q.  We have the mass and delta T.  So, we need the specific heat.  That is specific to the material, like density.  This is iron.  The specific heat of iron is 0.45 kJ/kg degC.  We have the delta T in Celsius.  We need the 2000 lbs. in kg.  Using Google's conversion for pounds to kg, 2000 pounds = 907.1847 kg.  So, plugging in the numbers:

Q = m*c*delT

= 907.1847*0.45*25

= 10,205.827875 kJ = 10,205,827.875 joules.

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