How many joules of heat are needed to raise the temperature of 20g of aluminum from 54^\circ ∘ c to 82^\circ ∘ c, if the specific heat of aluminum is 0.540 j/gc a. 302.4 j b. 29 j c. 1037 j d. 0.76 j

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.