Chemistry Reference
In-Depth Information
Chapter 6 Examination
1. [h. combustion]—Perhaps the easiest way to identify a combustion reaction
is to look for these products.
2. [f. hydrocarbon]
3. [g. synthesis]
4. [b. precipitate]
5. [a. spectator ion]
6. [CH
4
]—Begin by looking at which elements are missing, then concentrate
on how many atoms there are.
7. [NH
3
]—After awhile, many of these reactions will start to look familiar to you.
8. [KI]—A single replacement reaction.
9. [MgO]—A synthesis reaction.
10. [Ba(NO
3
)
2
]—A double replacement reaction.
11. [HCl]—Acids react with certain metals to generate hydrogen gas.
12. [decomposition]—The electrolysis of water.
13. [single replacement]—Notice how potassium replaces the other metal.
14. [combustion]—The hydrocarbon in this reaction is ethane.
15. [synthesis]—The synthesis of carbon dioxide.
16. [synthesis]—Of the five main types of reactions, the synthesis reaction is the
only one with a general formula that shows only one substance as a product.
17. [2AlPO
4
+ 3Ca(OH)
2
2Al(OH)
3
+ Ca
3
(PO
4
)
2
]—Start by trying to
balance the calcium, then look at the phosphate and hydroxide ions.
18. [C
2
H
4
+ 3O
2
2CO
2
+ 2H
2
O]—Start by balancing either the hydrogen or
the carbon. Balance the oxygen last.
19. [Fe
3
O
4
+ 4H
2
3Fe + 4H
2
O]—Start by adding the coefficient to the
water, in order to balance the oxygen. The rest should be easy.
20. [2Al(OH)
3
Al
2
O
3
+ 3H
2
O]—Start by adding the 2 coefficients in front of
the aluminum hydroxide, then focus on balancing the oxygen.
21. [H
2
0
+ Cl
2
0
2H
1-
Cl
1-
]—The reactants are both free elements, so they each
get an oxidation number of 0. On the product side, the chloride is a halogen,
so it must be -1. Hydrogen must be +1 to balance the chloride in a 1:1 ratio.
22. [Ag
1+
N
5+
O
3
2-
+ Cu
0
Cu
2+
(N
5+
O
3
2-
)
2
+ Ag
0
]—It helps to remember that
the nitrate ion (NO
3
-
) has a net charge of -1. Therefore, if the oxygen atoms
have a combined charge of -6, that leaves a charge of +5 for the nitrogen.
