Counting Atoms 1) NaOH
2) 4 HNO3
3) 4 Mg(OH)2
4) MgCl2
5) 4 Li2O
6) 2 NaOH
7) Li2SO4
8) 3 H2O
9) 4 Al2(SO3)3
10) NaC2H3O2
11) 3 Al2O3
13) NH4Cl
14) 5 ZnSO4
12) 2 (NH4)3PO4
15. How many different types of elements are there in the following compound: CH4
16. _E_Diamond (C) 17. _C_Sugar (C6H12O6)
18. _C_Sulfuric Acid (H2SO4)
20. _C_Water (H2O)
_24. C_Dry Ice (CO2)
21. _C_Alcohol (CH3OH)
25. _C_Baking Soda (NaHCO3)
22. C_Ammonia (NH3)
26. _E_Titanium (Ti) _27. E_Iron (Fe)
_23. C_Salt (NaCl) _ 28. _E_Gold (Au) _
19. _E_Krypton (K)
29. _E_Bismuth (Bi) _30. E_Uranium (U)
Classify the following as being a physical or chemical change. ____________________ 31. Sodium hydroxide dissolves in water. ____________________ 32. Hydrochloric acid reacts with potassium hydroxide to produce a salt, water, and heat. ____________________ 33. A pellet of sodium is sliced in two. ____________________ 34. Water is heated and changed into steam. ____________________ 35. Potassium chlorate decomposes to form solid potassium chloride and oxygen gas. ____________________ 36. Iron rusts. ____________________ 37. When place in H2O, a piece of sodium catches on fire as hydrogen gas is liberated and sodium hydroxide forms. ____________________ 38. Evaporation. ____________________ 39. Ice melting. ____________________ 40. Milk sours. ____________________ 41. Sugar dissolves in water. ____________________ 42. Wood rotting. ____________________ 43. Pancakes cooking on a griddle. ____________________ 44. Grass growing in a lawn. ____________________ 45. A tire is inflated with air. ____________________ 46. Food is digested in the stomach. ____________________ 47. Water is absorbed by a paper towel. ____________________ 48. Water freezing into ice.
49. Al 50. Fe
+ +
N2 → AlN O2 →
51 .
CaCO3 →
CaO +
52.
NH4NO3 →
N2 O
53.
KI
Cl2 →
+
Fe3O4
CO2
+ H2O KCl + I2
54. C6H6
+ O2 →
CO2
+
55.
Na + H2O → NaOH
56.
Fe +
FeCl3 -→
H2O + H2
FeCl2
57. KI 58. SO2 59. NaNO2 60. MgF2 61. CaCl2 62. Al2O3 63. B2S3 64. P4S5 65.
O2
66.
SeF6
67.
Si2Br6
68.
SCl4
69.
CH4
70.
B2Si
71.
NF3
72. What is an endothermic reaction? 73. What is an exothermic reaction? 74. What are the signs of a chemical reaction? 75. What happened to do the calcium chloride bag?
76. Explain how the baking soda and vinegar applies to the Law of Conservation of Mass.
Answer Key Counting Atoms 1) NaOH Na-1, O-1, H-1 2) 4 HNO3
H-4, N-4, O-12
3) 4 Mg(OH)2 Mg- 4, O-8, H-8 4) MgCl2 Mg- 1, Cl-2 5) 4 Li2O Li-8, O-4 6) 2 NaOH Na- 2, O-2, H-2 7) Li2SO4 Li-2, S-1, O-4 8) 3 H2O H-6, O-3 9) 4 Al2(SO3)3 Al-8, S-12, O-36 10) NaC2H3O2 Na-1, C-2, H-3, O-2 11) 3 Al2O3 Al-6, O-9 12) 2 (NH4)3PO4 N-6, H-24, P-2, O-8 13) NH4Cl N-1, H-4, Cl-1 14) 5 ZnSO4 Zn-5, S-5, O-20 15. How many different types of elements are there in the following compound: CH4 2 different elements- Carbon and Hydrogen Classify as either element or compound 16. _E_Diamond (C) _19. C_Water (H2O)
23. _C_Dry Ice (CO2) 24. _C_Baking Soda
17. _C_Sugar (C6H12O6)
18. _C_Sulfuric Acid (H2SO4)
_20. C Alcohol (CH3OH)
(NaHCO3)
21. C_Ammonia (NH3)
25. _E_Titanium (Ti) 26. _E_Iron (Fe)
22. _C_Salt (NaCl) 27. _ _E_Gold (Au)
28. _E_Krypton (K) 29. _E_Bismuth (Bi) 30. _E_Uranium (U)
Classify the following as being a physical or chemical change. ___Physical___________31. Sodium hydroxide dissolves in water. ___Chemical__________32. Hydrochloric acid reacts with potassium hydroxide to produce a salt, water, and heat. ___Physical___________33. A pellet of sodium is sliced in two. ___Physical___________34. Water is heated and changed into steam. __Chemical___________35. Potassium chlorate decomposes to form solid potassium chloride and oxygen gas. ___Chemical__________36. Iron rusts. ___Chemical_________ 37. When place in H2O, a piece of sodium catches on fire as hydrogen gas is liberated and sodium hydroxide forms. __Physical____________38. Evaporation. __Physical____________39. Ice melting. ____Chemical_________40. Milk sours. ___Physical__________ 41. Sugar dissolves in water. ___Chemical__________42. Wood rotting. ___Chemical_________ 43. Pancakes cooking on a griddle. ___Chemical__________44. Grass growing in a lawn. __Physical____________45. A tire is inflated with air. __Chemical___________46. Food is digested in the stomach. __Physical____________47. Water is absorbed by a paper towel. __Physical___________ 48. Water freezing into ice.
Balance the equations
49. 2Al
+
N2 → 2AlN
50.
3Fe
+
2O2
51.
CaCO3 →
CaO +
52.
NH4NO3 →
N2 O
53.
2KI
Cl2 →
54.
2C6H6
55.
2Na + 2H2O → 2NaOH
56.
Fe + 2FeCl3 -→
+
→
Fe3O4 CO2
Balanced
+ 2 H2O
+ 15O2 →
2KCl + I2 12CO2
3 FeCl2
57. KI Potassium iodide 58. SO2 Sulfur dioxide 59. NaNO2 Sodium nitrate 60. MgF2 Magnesium fluoride 61. CaCl2 Calcium chloride 62. Al2O3
Aluminum oxide
63. B2S3
Diboron sulfide
64. P4S5 tetraphosphorus pentasulfide 65.
O2 oxygen
66.
SeF6 selenium hexafluoride
67.
Si2Br6 disilicon hexafluoride
68.
SCl4 sulfur tetrachloride
69.
CH4 methane
70.
B2Si diboron silicide
+
6H2O
+ H2
71.
NF3 nitrogen trifluoride
72. What is an endothermic reaction? When a reaction absorbs heat 73. What is an exothermic reaction? When a reaction releases heat 74. What are the signs of a chemical reaction? Color change, odor, gas production 75. What happened to do the calcium chloride bag? Gas produced, changed color
76. Explain how the baking soda and vinegar applies to the Law of Conservation of Mass. The mass of the baking soda and vinegar was the same as when they mixed together.
