# Example problem how much heat is required to raise

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Example Problem:How much heat is required to raise the temperature of 10.0 g H2O from 25.0C to 35.0°C? (
How much heat is required to raise the temperature of 10.0 g of Cu from 25.0°C to 35.0°C? (
Chem 1036 Chapter 6 21 of 40
Chem 1036 Chapter 6 22 of 40
Chem 1036 Chapter 6 23 of 40Example Problem: A sample of iron pellets is heated to 99.4°C and dropped in 57.8 g of insulated water at 19.3°C. The final temperature is 28.4°C. What was the mass of the iron sample?
Chem 1036 Chapter 6 24 of 40Example Problem: 2.00 L of 0.500 MH2SO4(density = 1.030 g/mL) at 25.000°C is mixed with 200. g of a NaOH solution, also at 25.000°C. After stirring, the temperature of the solution is 36.820°C. Calculate qfor the reaction. (Assume the specific heat capacity of each solution is 4.184 J/g°C. ) Is the reaction exothermic or endothermic?
Chem 1036 Chapter 6 25 of 40Constant Volume (Bomb) CalorimetryUses a fixed volume, tightly sealed container which is not open to the atmosphere, so the volume does not change but the pressure changes when gases are involved.Used for exothermic reactions such as combustion. Can be used to determine the calorie content of food.The water in the calorimeter and the calorimeter material itself are considered the surroundings.q= m×c×TOR qsurroundings = Ccalorimeter×Tqsystem= −Ccalorimeter×TCcalorimeteris the heat capacity of the calorimeter which incorporates the mass and specific heat capacity of the calorimeter material andsometimes the water in thecalorimeter as well.Note: if Ccalorimeterdoes notinclude the water in the calorimeter, you use:qsystem= (−Ccalorimeter×T) + (−massH2O) ×cH2O×T
Chem 1036 Chapter 6 26 of 40
Chem 1036 Chapter 6 27 of 40