Change the following sentence into a chemical equation: "3 mole of aqueous Ca(OH)2 reacts with 2 moles of aqueous Al(NO3)3 to produce 2 mole of solid Al(OH)3
and 3 moles of aqueous Ca(NO3)2. Identify the reactants and products of the
reaction.

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

Aphysical change is one that you can put in and remove like a ham sandwich. the stuff you put in there can be changem its not permanet. a chemical change is on that can't be change thats permanet. like when you make a cake and bake it. you can't get those ingredients back.

While unproven, it uses facts to support part of a conclusion. it is still factual and has predictive power, however.