Question

The density of mercury is 13.5 g/ml and the density of water is 1.00 g/ml. if a mercury barometer reads 709 mmhg, what is the barometric pressure in cmh2o?

Answer 1

To convert 709 mm Hg to cm H₂O, first convert mm Hg to cm Hg and then multiply by 13.6 to account for the difference in density, resulting in a barometric pressure of 964.24 cm H₂O.

Step-by-step explanation:

To convert the pressure reading from a mercury barometer (mm Hg) to a water barometer reading (cm H₂O), we need to use the ratio of densities of mercury and water. Given that the density of mercury is approximately 13.6 times greater than the density of water, we can calculate the height of the water column that would exert the same pressure as the mercury column.

First, we convert the given pressure in mm Hg to cm Hg since the resulting pressure in water is to be found in cm H₂O. We know that 1 cm Hg = 10 mm Hg, so we have:

709 mm Hg * (1 cm Hg / 10 mm Hg) = 70.9 cm Hg

Now, to convert to cm H₂O, since the density of mercury is 13.6 times that of water, a column of water will need to be 13.6 times higher than a mercury column to exert the same pressure. Therefore:

Barometric pressure = 70.9 cm Hg * 13.6 = 964.24 cm H₂O

The barometric pressure in cm H₂O is 964.24 cm.

Answer 2

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