Question

44.90 g of reactants are placed in a beaker

containing 45.00 g of water at 15.00 oC. At the end of the chemical reaction the temperature of the water rises to 25.00 oC. Calculate the energy change of the reaction rounded to the correct number of sig figs.




A

1900 J


B

-1900 J


C

1882 J


D

-1882


E

1884 J


F

-1884 J



PLS help lol

Answer 1

D. -1882J

Step-by-step explanation:

We can solve the energy released in a chemical reaction in an aqueous medium using the equation:

Q = -m*C*ΔT

Where Q is energy (In J),

m is mass of water (45.00g)

C is specific heat of water (4.184J/g°C)

And ΔT is change in temperature (25.00°C - 15.00°C = 10.00°C)

Replacing:

Q = -45.00*4.184J/g°C*10.00°C

Q = -1882J

Right answer is:

D. -1882J