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My name is Ann [436]
3 years ago
14

According to the cooling curve, what is the approximate freezing point of the substance?

Chemistry
2 answers:
Dmitry_Shevchenko [17]3 years ago
6 0

Correct answer: B

Cooling curve is the plot of temperature versus time as the sample is allowed to cool. In a cooling curve, we start at a temperature greater than the boiling point. At this temperature, the sample is in gaseous state. At the boiling point, there is no change in temperature as the gaseous and liquid states are in equilibrium. As the temperature reduces further, the liquid starts to condense and at the melting point of the sample the liquid undergoes phase transition to solid state. At the melting temperature, a second plateau is observed as the temperature remains unchanged. At temperatures below the melting point, the sample exists as a solid.

So from the curve, the second plateau is observed at around -111^{0}C. This point represents the phase transition from liquid to solid state.

Vilka [71]3 years ago
5 0

Answer:

Its B broooooooo

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8 0
3 years ago
If 1,000 mL = 1 L, which of the following are possible conversion factors for liters and milliliters? Check all that apply.
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Answer:

Two conversion factors:

         1=\dfrac{1L}{1,000ml}\\ \\ \\ 1=\dfrac{1,000mL}{1L}

Explanation:

You can create two possible <em>conversion factors</em>, one to convert from mL to L, and one to convert from L to mL

<u />

<u>a) From mL to L</u>

To convert mL to L you need to multiply by a conversion factor that has mL on the denominator and L in the numerator.

Your starting point is: 1,000mL=1L

Then, divide both sides by 1,000mL (this will be on the denominator of the fraction);

       1,000mL=1L\\\\ \\\dfrac{1,000ml}{1,000mL}=\dfrac{1L}{1,000mL}\\ \\ \\ 1=\dfrac{1L}{1,000mL}

<u>b) From L to mL</u>

Divide both sides by 1 L:

            1,000mL=1L\\\\ \\\dfrac{1,000ml}{1L}=\dfrac{1L}{1L}\\ \\ \\ 1=\dfrac{1,000mL}{1L}

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Question 7 of 10
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Answer:

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see explanation

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