Question

what is the δh of a reaction where the mass of the solution is 18.7 g at a specific heat of 5.008 j/g°c and the system experiences a change in temperature of 7.2°c? -674.27 j -67.42 j 67.42 j 674.27 j

Explanation:

Step1: Use the heat formula

The formula for heat \(q = mc\Delta T\), where \(m = 18.7\space g\), \(c=5.008\space J/g^{\circ}C\), \(\Delta T = 7.2^{\circ}C\).

Step2: Calculate the heat value

Substitute the values into the formula: \(q=18.7\times5.008\times7.2\).
First, \(18.7\times5.008 = 93.6496\).
Then, \(93.6496\times7.2=674.27\space J\).
Since this is a reaction (assuming it is exothermic as per the sign convention in thermochemistry for reaction enthalpy when heat is released), \(\Delta H=-q\).

Answer:

-674.27 J