Susie places 3 beakers in the freezer. The first beaker contains water only, the second contains water and salt, and the third c
ontains a water and sugar solution. Susie recorded the temperature and the time at which each mixture froze. Which is the most appropriate hypothesis for her experiment? A) Salt affects the freezing point of water. B) The addition of salt raises the freezing point of water. C) The addition of a sugar lowers the freezing point of water. D) The addition of different substances affects the freezing point of water.
The correct answer is option D) "The addition of different substances affects the freezing point of water".
Explanation:
A hypothesis is defined as a supposition based on evidence that could be confirmed or rejected according to experimental results. In this case, Susie has performed an experiment that involves freezing 3 beakers and recording the temperature and time of freezing. The first beaker contains water, the second water and salt, and the third water and sugar. Since Susie is experimenting with salt and sugar using a water only beaker as control, the most appropriate hypothesis for her experiment is that the addition of different substances affects the freezing point of water. There is no additional information that could make Susie hypothesize how salt and sugar affects the freezing point of water, but the results of her experiment will let her gather the information she needs.
D) The addition of different substances affects the freezing point of water.
Explanation:
The best answer would be letter D.
The short explanation would be, the other choices only involves the addition of 1 substance (salt or sugar).
The long explanation:
Susie is testing two types of solution: <u>sugar + water</u> and <u>salt + water. </u>This means that she is testing the effect of both. An experiment is done to test certain variables and an addition of a variable that is not being tested is not advisable. But since she intentionally used both solutions, then it is reason enough to assume that she is testing both substances (sugar and salt) so the hypothesis should include both as well.
In mollusks with shells, the outer cells of the mantle secrete
calcium carbonate and conchiolin to form the shell. The mantle is the body wall
of a mollusk. It resides below the shell where it covers the body of the
animal.
