Question

the combustion of 4.00 grams of milk in a bomb calorimeter resulted in a temperature increase of 3.4 °c. δh_comb = -210.7 j/g what is the heat of reaction? q_comb = ? j enter either a + or - sign and the magnitude.

Explanation:

Step1: Recall the formula for heat of combustion

The heat of combustion \( q_{\text{comb}} \) is given by the product of the mass \( m \) of the substance and the heat of combustion per gram \( \Delta H_{\text{comb}} \). The formula is \( q_{\text{comb}} = m\times\Delta H_{\text{comb}} \).

Step2: Substitute the given values

We are given that \( m = 4.00 \, \text{g} \) and \( \Delta H_{\text{comb}}=- 210.7 \, \text{J/g} \). Substituting these values into the formula:
\( q_{\text{comb}}=4.00\,\text{g}\times(- 210.7\,\text{J/g}) \)

Step3: Calculate the result

\( 4.00\times(-210.7)=- 842.8 \) (We multiply the mass and the heat per gram. The negative sign indicates that the reaction is exothermic, releasing heat.)

Answer:

\(-842.8\)