Find the heat content per gram of peanut

[y_foss]

Can some one help me with these two questions? I am unclear how to do them! Thanks

1. A 27.2g peanut is burned in a bomb calorimeter, and the temperature of the surrounding 100g of water rises from 24.25 degrees C to 26.87 degrees C. Given that the calorimeter constant is 2.23kJ/degrees C, find the heat content per gram of peanut.

2. When 10.0g of water at 90.0 degrees C is added to 100 g of water at 10.0 degrees C in a well-insulated calorimeter, what is the final temperature of the mixture? Assume that all of the heat lost by the hot water is gained by the cold water, and vise versa.

 

[Gokul43201]

H = m*C*[T(final) - T(initial)] where m : mass, C : specific heat capacity, T : temperature
m*C is referred to as the heat capacity, C', which is specified for the calorimeter ( C' = 2.23kJ/C)

1. Find the value of C(water) - try Google (if you don't know it). Now you have enough information to find the heat absorbed by the water. Since the calorimeter is in equilibrium with the water, you may assume that it undergoes the same temperature change as the water. So, you can calculate the heat absorbed by the calorimeter. The sum of these two numbers is the total heat released by burning the peanut. Dividing this by the weight of the peanut gives it's calorific value (or heat content per gram).

2. Heat lost by A = heat gained by B. You know the values of m1, m2, C, T1(initial), T2(initial). When mixed, A and B reach the same final temperature T(final). Plug in all the nhumbers and solve to find T(final).

 

[ravenprp]

1. To find the heat content per gram of peanut, we need to use the equation Q = mCΔT, where Q is the heat content, m is the mass, C is the specific heat capacity, and ΔT is the change in temperature. First, we need to calculate the heat released by the peanut by using the equation Q = Ccal * ΔT, where Ccal is the calorimeter constant and ΔT is the change in temperature of the surrounding water. So, Q = 2.23 kJ/degrees C * (26.87 degrees C - 24.25 degrees C) = 5.88 kJ. Next, we need to calculate the mass of the peanut that was burned by subtracting the mass of the water from the total mass of the bomb calorimeter and peanut, which is 27.2g - 100g = -72.8g. This negative value indicates that 72.8g of the peanut was burned. Finally, we can calculate the heat content per gram of peanut by dividing the heat released (5.88 kJ) by the mass of the peanut (72.8g). Heat content per gram of peanut = 5.88 kJ/72.8g = 0.0806 kJ/g.

2. To find the final temperature of the mixture, we can use the equation Qhot = Qcold, where Qhot is the heat lost by the hot water, and Qcold is the heat gained by the cold water. We can calculate Qhot by using the equation Qhot = mhot * C * ΔT, where mhot is the mass of the hot water, C is the specific heat capacity of water, and ΔT is the change in temperature. Similarly, we can calculate Qcold by using the equation Qcold = mcold * C * ΔT, where mcold is the mass of the cold water. Since we know that Qhot = Qcold, we can set the two equations equal to each other and solve for the final temperature, Tfinal. So, mhot * C * (Tfinal - 90.0 degrees C) = mcold * C * (Tfinal - 10.0 degrees C). We can simplify this equation to Tfinal = (mhot * 90.0 degrees C + mcold * 10.0 degrees C) / (mhot + mcold). Pl