Describe the difference between the terms “element”, “compound”, “molecule”, and “salt”.

You can define an element as a substance with only one type of atom in (e.g. only sulphur atoms). If a substance has more than one type of atom in, then it is either a compound or a mixture, depending on whether the elements have bonded. Examples of elements are:

Oxygen
Sulphur
Carbon
Hydrogen
Protactinium

Compound-
A substance made up of atoms of two or more different elements joined by chemical bounds.
Molecule- a pure substance that cannot be broken down
Salt- A Ionic Compound Formed From The Reaction Of An Acid And Base .

I'm not sure but i will try to find out

the catch is that the top numbers are atomic masses the bottom numbers are the numbers of protons and electrons in an uncharged atom. they are the number of that atoms as you would find them on the periodic table. further, the numbers on the left are used to determine the missing numbers on the right

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer