Final answer:
When multiplying 1.0030 ml by 2.5 L by 0.00159 ml, the product should have 2 significant figures because the least precise factor (2.5 L) has 2 significant figures.
Step-by-step explanation:
The number of significant figures in a calculated product or quotient is determined by the factor with the least number of significant figures. In multiplying 1.0030 ml (5 significant figures) by 2.5 L (2 significant figures) by 0.00159 ml (3 significant figures), we first need to convert all units to the same base, which here is milliliters (mL). One liter is 1,000 mL, so to convert 2.5 L to mL, we multiply by 1,000 moving the decimal point three places to the right, which gives us 2,500 mL. However, this number has significant figures equal to the original liters value, as the conversion from liters to milliliters is an exact number and does not affect the number of significant figures. Therefore, we retain 2 significant figures, making the value 2.5 x 103 mL.
When we calculate the product of these three values, the result must be reported using the smallest number of significant figures from any of the factors, which here is 2. So, the final answer would be reported with 2 significant figures.