Enthalpy of a Phase Change Part A) Calculate the enthalpy change, ΔH, for the process in which 29.0 g of water is converted from liquid at 17.7 ∘C to vapor at 25.0 ∘C . For water, ΔHvap = 44.0 kJ/mol at 25.0 ∘C and Cs = 4.18 J/(g⋅∘C) for H2O(l).

Part B) How many grams of ice at -20.4 ∘C can be completely converted to liquid at 11.7 ∘C if the available heat for this process is 4.24×103 kJ ?

For ice, use a specific heat of 2.01 J/(g⋅∘C) and ΔHfus=6.01kJ/mol .

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.

under a microscope, cancer cells may look very different from normal cells. they often have different sizes and some may be larger than normal while others are smaller. cancer cells are often abnormally shaped and the control centre of the cell (the nucleus) may have an abnormal appearance.

i think? ?

because natural gas is colorless, odorless, and tasteless, distributors add mercaptan (a chemical that smells like sulfur) to give natural gas a distinct unpleasant odor (it smells like rotten eggs). they locate the types of rock that are likely to contain natural gas deposits.