Which substance has a mass is 13.5 grams, and its volume is 5 cm 3.

Substance is Aluminium

Explanation:

We are given;

Mass; m = 13.5 grams

Volume; V = 5 cm³

Formula for density is;

density = m/V

Density = 13.5/5

Density = 2.7 g/cm³

From the table attached, we can see that the element with a corresponding density of 2.7 is Aluminium

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.  

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