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Crazy boy [7]
3 years ago
6

In the recrytallization / melting point lab, there are a number of experimental details that need to be followed. Choose whether

the following statements are true or false.
a. If a mercury or alcohol thermometer is used in a melting point determination, it should be read to the nearest whole degree, a fractional degree reading is not possible.
b. A slow heating rate is necessary near the expected melting point A too bulky sample will cause an artificially long melting point range.
c. In some melting point instruments, the sample is placed on a microscope slide which is then placed on top of a heated metal block, and the temperature of the metal block is raised until melting is observed.
d. If the sample to be melted were placed on a microscope slide then heated, finger oils on the microscope slide will lower the melting point.
Chemistry
1 answer:
Zarrin [17]3 years ago
6 0

Answer:

I think the answer is A.

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Andru [333]

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<h3>Further explanation</h3>

Given

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Required

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\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{t/t\frac{1}{2} }}}

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nalin [4]

Answer:

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