How many times stronger is the hydrogen-ion concentration of a pH 4 solution as compared with a pH 9 solution?
0.00001
5
100,000
50
Correct Answer : C
The correct answer is c. 100,000. The pH scale is a logarithmic scale, which means that each change of one pH unit represents a tenfold change in the hydrogen-ion concentration. A pH 4 solution has a hydrogen-ion concentration that is 10^5 (or 100,000) times greater than that of a pH 9 solution.
a. 0.00001 is the hydrogen-ion concentration of a pH 9 solution as compared with a pH 4 solution.
b. 5 is the difference in pH units between a pH 4 solution and a pH 9 solution.
d. 50 is not the correct answer.
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Explanation
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Explanation
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Explanation
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Correct Answer is A
Explanation
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Explanation
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The other options are not correct because they do not accurately describe the triple point of a substance. Sol, gel, and plasma are not phases that coexist at the triple.
Correct Answer is D
Explanation
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B. A substance with a pH of 3 is not 10 times more alkaline than a substance with a pH of 4.
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Correct Answer is A
Explanation
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Correct Answer is A
Explanation
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D. Soap’s texture does not physically scour grime off surfaces.
Correct Answer is B
Explanation
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Correct Answer is B
Explanation
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