Answer:

Explanation:
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In this case, since it is observed that hot cadmium is placed in cold water, we can infer that the heat released due to the cooling of cadmium is gained by the water and therefore we can write:

Thus, we insert mass, specific heat and temperatures to obtain:

In such a way, since the specific heat of cadmium and water are respectively 0.232 and 4.184 J/(g °C), we can solve for the equilibrium temperature (the final one) as shown below:

Now, we plug in to obtain:

NOTE: since the density of water is 1g/cc, we infer that 25.00 cc equals 25.00 g.
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Answer:
Number of moles (n)=
molecular weight
weight
Weight=n×Molecular weight
=0.5×14
Mass=7g
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Bromine can be classified as a pure substance.
Why?
Bromine is an element with atomic number 35 on group 17 of the Periodic Table. That's the first sign that shows us that it is a pure substance.
But the fact that it has a clear and defined boiling and melting point is a sign that we are in the presence of a pure substance. Pure substances are characterized by defined boiling and melting points.
Mixtures usually have a range of temperatures in which they melt and boil.
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