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astra-53 [7]
3 years ago
7

In an experiment, onion plants of different ages were exposed to various amounts of caffeine to determine the effect of caffeine

on cell growth. Temperature, amount of water, and light were kept constant. Which of these statements about the experiment is definitely true?
a. The results may not be valid because there were two variables.
b. The amount of caffeine used was a control.
c. Temperature, water, and light were the only variables.
d. Onion plants can be used to model the effects of caffeine on living things.
Chemistry
1 answer:
VladimirAG [237]3 years ago
5 0
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
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Answer:

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Explanation:

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d=\frac{10g}{6cm^{3} }

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Rounded to 3 significant figures, the density of the block of brown sugar is 1.67 g/cm3. If the mass is in grams and the volume is in cm3, the unit for the final answer is \frac{g}{cm^{3} } (grams per centimetres cubed).

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Answer:

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Explanation:

Hello!

In this case, since the molarity of a solution is defined in terms of the moles of the solute and the volume of solution, given that the concentration of Cu(NH₃)₄²⁺ is 0.041 M, and there is only one copper atom per Cu(NH₃)₄²⁺ ion, we can compute the concentration of Cu²⁺ as shown below:

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