In lab, a student weighed a new 10mL syringe and found it’s mass to be 25.5678 g. After filling it with a solution to the 10.0 mL mark, the new mass of the syringe with solution was 35.9888 g. What is the density of the solution inside the syringe with correct significant figures?
35.9888 g filled to the 10.0 mL mark
-25.5678 g empty
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10.4210 g is mass of the 10.0 mL sample
density = mass/volume = 10.4210/10.0 = 1.04210 g/mL BUT that isn't the correct number of significant figures. You have six places in the mass and dividing by 3 places in the volume. In division you may have as many significant figures in the answer as the SMALLEST number in the two values divided; therefore, you may have 3 places so that will be 1.04 g/mL.