A 136 g sample of an unknown substance was heated from 20.0 °C to 40.0 °C. In the process the substance absorbed 2440 J of energy. What is the specific heat of the substance? Identify the substance among those listed in Table 2. A. the specific heat is 0.897 J/g. C, The Substance is aluminum
B. the specific heat is -0.897 J/g. C, The Substance is aluminum
C. the specific heat is 4.184 J/g. C, The Substance is water
D. there's not enough information to determine which is the substance.

Option A. The specific heat is 0.897 J/gºC, The Substance is aluminum.

Explanation:

We'll begin by calculating the change in temperature of the substance. This can be obtained as follow:

Initial temperature (T₁) = 20.0 °C

Final temperature (T₂) = 40.0 °C

Change in temperature (ΔT) =?

ΔT = T₂ – T₁

ΔT = 40 – 20

ΔT = 20 °C

Finally, we shall determine the specific heat capacity of the substance. This can be obtained as follow:

Mass (M) = 136 g

Change in temperature (ΔT) = 20 °C

Heat (Q) absorbed = 2440 J

Specific heat capacity (C) =?

Q = MCΔT

2440 = 136 × C × 20

2440 = 2720 × C

Divide both side by 2720

C = 2440 / 2720

C = 0.897 J/gºC

Comparing the specific heat capacity (i.e 0.897 J/gºC) of the substance with those in the table above, the substance is Aluminum.

Thus, option A gives the correct answer to the question.

hi my dude or dudette

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.