Hello!
Antifreeze says it in the name. This means that it helps prevent freezing. The liquid that would freeze if you wouldnt use the antifreeze is water. This means that the antifreeze has to have a higher freezing point then water, because otherwise it would only freeze faster!
Hope this helped you!
1. From grams -> mole:
=grams given x 1 mol/molar mass
So 150 g Cu x 1 mol Cu/63.546 g Cu = 2.4 mol Cu
2. From mole -> atoms
=number of mol x 6.022x10^22 atoms/1 mol
So 2.4 mol Cu x 6.022x10^22 atoms Cu/1 mol Cu = 1.4 x 10^24 atoms Cu
physical change in a substance doesn't change what the substance is. In a chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed. For example, if a piece of paper is cut up into small pieces it still is paper.
