An unknown substance has a mass of 15.5 g . When the substance absorbs 1.395×102 J of heat, the temperature of the substance is raised from 25.0 ∘C to 45.0 ∘C . What is the most likely identity of the substance?

iron (Fe)

Explanation:

Use q = mcΔT.

q = 1.396 x 10^2 J

m = 15.5g

ΔT = (45.0 - 25.0) = 20 degrees celcius

1.396 x 10^2 = 15.5 x c x 20

c = .450 J/g x degrees celcius

This is closest to the specific heat of iron/steel.

c is the answer because when something is left after something evaporates that shows the chemical change.

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.