5TH GRADE SCIENCE Listed below are the four phase changes. Which two phase changes occur when heat is lost?

A. Freezing
B. Evaporation
C. Condensation
D. Melting

Phase changes that require a loss in energy are condensation and freezing.

Explanation:

freezing consensation

Explanation:

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.