The hypothesis is that salt water freezes faster than fresh water.
The dependent variable is time taken for ice to appear.
The independent variable is presence or absence of salt
The constants are the amount of water in each tray, freezing conditions and length of time of exposure to freezing condition.
The control group is the tray to which salt was not added
The experimental group is the tray to which salt was added
The presence of solutes in a solution causes the freezing point depression.
A solution is made up of a solute and a solvent. In the presence of a solute, the freezing point of a pure solvent is decreased. This is because freezing point is a colligative property.
Colligative properties depend on the amount of solute present.
Hence, the pure water freezes faster (ice begin to appear earlier) than the salt water.
The hypothesis put forward in this experiment was found to be invalid by the experiment.
For more about colligative properties, see
brainly.com/question/10323760
The answer is A track star speeding up as he sprints to the finish line.
Answer:
Storage battery oe cell
Explanation:
The storage battery or cell is a device that coverts chemical energy into light energy when required.
During charging of battery, there is some chemical changes in the battery and absorb energy. The absorbed energy is converted into electrical energy when connected to an external load.
Hence, the correct answer is "Storage battery or cell".
Answer:
The correct option is b. an amino-terminal signal
Explanation:
A polypeptide that will eventually fold to become an ion channel protein, it means a kind of integral membrane protein, has an amino terminal signal that indicates its delivery to endoplasmic reticulum (ER) and then to the membrane. This type of signal usually consist in a nucleus of 6 to 12 aminoacids and one or more basic aminoacids. Once the polypeptide enters the ER, this signal is removed.
Answer:
15.98 L
Explanation:
First, you need to find T1, T2, V1 and V2.
T1 = 25 C = 298.15 K (25C + 273.15K)
T2 = 100 C = 373.15 K (100C + 273.15K)
V1 = 20. L
V2 = ? (we are trying to find)
Next, rearrange to fit the formula
V2 = V1 x T1 / T2
Next, fill in with our numbers
V2 = 20. L x 298.15 K / 373.15 K
Do the math and you should get...
15.98 L
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