The smaller pieces are less dense than the larger piece that remains.
The density of a substance is calculated as follows;
[tex]\rho = \frac{m}{V}[/tex]
where;
Since the pore volume of the rocks are the same, their densities is compared as follows;
[tex]\rho _1 = \frac{m_1}{V} \\\\\rho_2 = \frac{2m_1}{V} \\\\\rho _2 = 2 (\frac{m_1}{V})\\\\\rho_2= 2\rho _1[/tex]
Thus, density depends on mass and the smaller pieces are less dense than the larger piece that remains.
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