A. is definitely true. The age of the plants and the amount of caffeine are two variables. The experimenter should have used only plants of the same age in order to determine the effect of caffeine.
b. is wrong. The amount of caffeine used was a variable.
c. is wrong. Temperature, water, and light were constants.
d. is wrong. The statement is a hypothesis that the experiment is trying to prove
Answer:
- <u>b. three half-lives</u>
Explanation:
The number of half-lives elapsed, n, is calculated dividing the time by the half-life time:
- n = time / half-life time
<u>a. A sample of Ce-141 with a half-life of 32.5 days after 32.5 days</u>
- n = 32.5 days / 32.5 days = 1 half-life
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<u>b. A sample of F-18 with a half-life of 110 min after 330 min</u>
- n = 330 min / 110 min = 3 half-lives
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<u>c. A sample of Au-198 with a half-life of 2.7 days after 5.4 days</u>
- n = 5.4 days / 2.7 days = 2 half-lives
Answer:
For a good consert mix aggregate needed to the clean hard strong partical free of absorb chemicals or coating clay and other fine materials
Answer:
.5 M
Explanation:
molarity = moles / liters
2.5/5 = .5 M
