Final answer:
The blood pressure device contains 95.2 grams of mercury, calculated using the density of mercury (13.6 g/ml) and the volume of mercury in the device (7.0 ml).
Step-by-step explanation:
To find out how many grams of mercury are present in a blood pressure device that holds 7.0 ml of mercury, we need to use the density of mercury.
Firstly, the density of mercury is a well-known constant, approximately 13.6 g/ml. This means that for every milliliter of mercury, it weighs 13.6 grams. To find the mass of the mercury in the device, we multiply the volume by the density:
Mass = Density × Volume
Mass = 13.6 g/ml × 7.0 ml
Mass = 95.2 grams of mercury
Therefore, the blood pressure device contains 95.2 grams of mercury.