1. A tentative explanation for a set of observations that can be tested by further
experimentation is referred to as
A) a hypothesis. B) a law. C) a theory. D) none of the above.
Ans: A Category: Easy Section: 1.2
2. A concise verbal or mathematical statement of a relationship between phenomena that is
always the same under the same conditions is referred to as
A) a hypothesis. B) a law. C) a theory. D) none of the above.
Ans: B Category: Easy Section: 1.2
3. A unifying principle that explains a body of facts and relations is referred to as
A) a hypothesis. B) a law. C) a theory. D) none of the above.
Ans: C Category: Easy Section: 1.2
4. Complete the following sentence. A hypothesis is
A) a tentative explanation for a set of observations that can be tested by further
experimentation.
B) a statement describing a relationship between phenomena that is always the same
under the same conditions.
C) a unifying principle that explains a body of facts and relations.
D) a model used to visualize the invisible.
Ans: A Category: Easy Section: 1.2
5. Complete the following sentence. A scientific law is
A) a tentative explanation for a set of observations that can be tested by further
experimentation.
B) a statement describing a relationship between phenomena that is always the same
under the same conditions.
C) a unifying principle that explains a body of facts and relations.
D) a model used to visualize the invisible.
Ans: B Category: Easy Section: 1.2
6. Complete the following sentence. A theory is
A) a tentative explanation for a set of observations that can be tested by further
experimentation.
B) a statement describing a relationship between phenomena that is always the same
under the same conditions.
C) a unifying principle that explains a body of facts and relations.
D) a model used to visualize the invisible.
Ans: C Category: Easy Section: 1.2
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uj
, Chapter 01: Introduction uj uj
7. Choose the response that includes all the items listed below that are pure substances.
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i. orange juice ii. steam iii. ocean water iv. oxygen v. vegetable soup
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A) i, iii, v B) ii, iv C) i, iii, iv D) iv only
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E) all of them are pure Ans: B Category: Easy u j uj uj uj uj uj u j u j
Section: 1.2 u j
8. Which of the following is an example of a physical property?
uj uj uj uj uj uj uj uj uj uj
A) corrosiveness of sulfuric acid uj uj uj
B) toxicity of cyanide uj uj
C) flammability of gasoline uj uj
D) neutralization of stomach acid with an antacid uj uj uj uj uj uj
E) lead becomes a liquid when heated to 601 C A
uj uj uj uj uj uj uj uj
ns: E Category: Easy
u j Section: 1.4 u j u j
9. Which one of the following is an example of a physical property?
uj uj uj uj uj uj uj uj uj uj uj
A) dynamite explodes D) ice floats on top of liquid water uj uj uj uj uj uj uj
B) meat rots if it is not refrigerated E) a silver platter tarnishes
uj uj uj uj uj uj uj uj uj
C) gasoline burns uj
Ans: D Category: Easy Section: 1.4
u j u j u j
10. Which one of the following represents a physical change?
uj uj uj uj uj uj uj uj
A) water, when heated to 100 C, forms steam uj uj uj uj uj uj
B) bleach turns hair yellow uj uj uj
C) sugar, when heated, becomes brown uj uj uj uj
D) milk turns sour uj uj
E) apples, when exposed to air, turn brown uj uj uj uj uj uj uj
Ans: A Category: Easy Section: 1.4
u j u j u j
11. All of the following are properties of sodium. Which one is a physical property of s
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odium?
A) It is a surface turns black when first exposed to air.
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B) It is a solid at 25 C and changes to a liquid when heated to 98 C.
uj uj uj uj uj uj uj uj uj uj uj uj uj uj
C) When placed in water it sizzles and a gas is formed. uj uj uj uj uj uj uj uj uj uj
D) When placed in contact with chlorine it forms a compound that melts at 801 C.
uj uj uj uj uj uj uj uj uj uj uj uj uj
E) Sodium is never found as the pure metal in nature. uj uj uj uj uj uj uj uj uj uj
Ans: B Category: Easy Section: 1.4
u j u j u j
12. All of the following are properties of tin. Which one is a chemical property of tin?
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A) Tin can be hammered into a thin sheet.
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B) At –40 C a sheet of tin crumbles to a gray powder.
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C) Tin melts at 231.9 C. uj uj uj
D) When a bar of tin is bent, it emits an audible “cry”. uj uj uj uj uj uj uj uj uj uj uj
E) Tin erodes when added to hydrochloric acid, and a clear gas forms. A
uj uj uj uj uj uj uj uj uj uj uj uj
ns: E Category: Medium
u j Section: 1.4 u j u j
Page 2 uj
, Chapter 01: Introduction uj uj
13. Which one of the following represents a chemical change?
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A) boiling water to form steam uj uj uj uj
B) burning a piece of coal uj uj uj uj
C) heating lead until it melts uj uj uj uj
D) mixing iron filings and sand at room temperature uj uj uj uj uj uj uj
E) breaking glass uj
Ans: B Category: Medium Section: 1.4
u j u j u j
14. Which of the following does not represent a chemical change?
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A) a freshly cut apple turns brown
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B) milk turns sour on standing at room temperature uj uj uj uj uj uj uj
C) when cooled to 0 C, liquid water becomes ice uj uj uj uj uj uj uj
D) frying an egg uj uj
E) fermentation of sugar to alcohol Ans uj uj uj uj uj
: C Category: Easy
u j Section: 1.4 u j uj
15. The SI prefixes nano and deci represent, respectively:
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A) 10–9 and 10–6. D) 109 and 10–6.
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B) 106 and 10–3. ujE) 10–9 and 10–1. uj uj uj uj uj uj
3 –3
C) 10 and 10 . uj uj uj
Ans: E Category: Easy Section: 1.7
u j u j
16. The SI prefixes milli and mega represent, respectively:
uj uj uj uj uj uj uj
A) 106 and 10–6. ujD) 10–3 and 109. uj uj uj uj uj
B) 10–3 and 106. E)
uj uj 10–6 and 10–3. uj uj uj uj uj
3 –6
C) 10 and 10 . uj uj uj
Ans: B Category: Easy Section: 1.7
u j u j
17. The SI prefixes kilo and centi represent, respectively:
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A) 103 and 10–2. uj D) 10–6 and 102. uj uj uj uj uj
–1
6
B) 10 and 10 . uj E) 102 and 10–3. uj uj uj uj uj
C) 10–3 and 10–2. uj uj uj uj
Ans: A Category: Easy Section: 1.7
u j
18. A nanometer corresponds to:
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A) 10–2 meters. D) uj uj 10–9 meters.uj uj
B) 10–3 meters. E) uj uj 10–12 meters.
uj uj
–6
C) 10 meters. uj uj
Ans: D Category: Easy Section: 1.7
u j u j u j
19. A microliter corresponds to:
uj uj uj
A) 10– 2 liters. B) 10– 3 liters. C) 10– 6 liters. D) 10– 9 liters. E) 10–
uj uj u j uj uj u j uj uj u j uj uj uj
12
uj liters. Ans: C Category: Easy Section: 1.7
uj uj u j u j u j
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