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We have a bomb calorimeter with a heat capacity of 555 J/K. In this bomb, we place 1000.0 mL of water. 2.046 g of a solid are burned in the bomb calorimeter. The temperature of the bomb and the water increases by 2.28 oC. The molar mass of this solid is 533.4 g/mol. How much heat would be released (in kJ, and note that we want the amount of heat released) if we burned 0.148 mol of this solid in the bomb calorimeter? The specific heat of water is 4.184 J/K/g. Make the approximation that the density of water is 1.00 g/mL.

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FInal answer:

The amount of heat released when burning 0.148 mol of the solid in the bomb calorimeter is approximately 18.3 kJ.

Step-by-step explanation:

In a bomb calorimeter, the heat released during a reaction is determined by the temperature change of the surrounding water. The formula to calculate the heat released (q) is given by the equation q = mcΔT, where m is the mass of water, c is the specific heat of water, and ΔT is the temperature change.

First, we need to find the mass of water (m) in grams. Given that the density of water is 1.00 g/mL and the volume is 1000.0 mL, the mass of water is 1000.0 g.

Next, we use the temperature change (ΔT), which is 2.28 °C. The specific heat of water (c) is 4.184 J/K/g. Plugging in these values into the formula, we get q_water = (1000.0 g) * (4.184 J/K/g) * (2.28 °C) = 9568.32 J.

Now, since we know the molar mass of the solid (533.4 g/mol), we can find the mass of the solid burned (2.046 g) corresponds to 2.046 g / 533.4 g/mol = 0.00384 mol.

To find the heat released per mole, we divide the heat released by the moles of the substance: q_per_mol = 9568.32 J / 0.00384 mol = 2493787.5 J/mol.

Finally, to find the heat released when burning 0.148 mol, we multiply the heat released per mole by the number of moles: q_final = 2493787.5 J/mol * 0.148 mol = 369172.05 J. Converting this to kilojoules, we get 369172.05 J / 1000 = 369.17 kJ, which can be rounded to approximately 18.3 kJ.

User Markc
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Step 1: Calculate the moles of the initial solid.

2.433g divided by 533.5g/mol = 0.00456mol

Step 2: Calculate heat released.

(1000g * 4.184J/g C* 2.30 C) + (555J/K *2.30 C) all divided by 0.00456mol

Multiply answer by (1kJ/1000J) =2390.3kJ/mol

Step 3: Calculate the amount of heat if 0.172 moles are burned

Q = 2390.3kJ/mol * 0.172moles = 411.1kJ
User Hoby
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