The mass of an empty flask plus stopper is 44.232 g. When the flask is completely filled with water the new mass is 153.617 g. The flask is emptied and dried, and a piece of metal is added. The mass of the flask, stopper and metal is 143.557 g. Next, water is added to the flask containing the metal and the mass is found to be 226.196 g. What is the density of the metal (in g/cm3) to the proper number of significant figures

3.7136g/cm³

Explanation:

Density is defined as the ratio between mass of a substance and its volume.

First, we will find the mass of the piece of the metal that is the difference between mass of metal + flask and mass of empty flask. That is:

Mass metal:

143.557g - 44.232g = 99.325g of the metal

Now, to find its volume you must know first the volume of the flask that can be obtained from the mass of water in the filled flask, that is:

153.617g - 44.232g = 109.385g of water = cm³ of water

In the second experiment, the mass of water = its volume is:

226.196g - 143.557g = 82.639g = 82.639cm³ of water

That means the volume the piece of metal is occupying is:

109.385cm³ - 82.639cm³ = 26.746cm³ of piece of metal

And its density is:

99.325g / 26.746cm³ =

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