Chem Think; Chemical Reactions

Chemical reactions

1. Reactants
2. Products
3. Chemical change has taken place
4. There is rearrangement of the bonds
5. Breaking or forming
6. Same atoms
7. Missing atoms or new atoms
8. Rearrange the bonds
9. 2 2 1 1
10. 2 H(2) and 1O(2)--> 1H2O

# of atoms in reactants	element	#of atoms in products
4	H	2
2	O	1

11. Law of Conservation of Mass
12. Cu atoms and Oxygen atoms
13. 2 Cu+0(2)--> 2CuO
14.

reactants	products
Cu atoms= 1	Cu atoms= 2
O atoms= 2	O atoms= 2

15. 1 Cu atoms,
16. O, Cu, Cu
17. 2 Cu+ 2O---> 2CuO

reactants	products
Cu atoms= 2	Cu atoms= 2
O atoms= 2	O atoms= 2

18. 1CH(4) + 2O(2)--> 2H(2)O+1CO(2)

atoms in reactants	element	atoms in products
1	C	1
4	H	2
2	O	3

19. 1 N(2) + 3H(2)--> 2NH(3)
20. 2 KCIO(3) ---> 2 KCI + 3 O(2)
21. 4 Al + 3 O(2)---> 2 Al(2)O(3)

Summary:

1. Chemical reactions always involve breaking bonds, making bonds, or both.
2. The same atoms must be present before and after the reaction.
3. You change the coefficients in front of each substance until there are the same number of each type of atom in both reactants and products.