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Question
If 1·71 g of sugar (molar mass = 342) are dissolved in 500 ml of an aqueous solution at 300 K, what will be its osmotic pressure?
Solution
Given:
mass of sugar = 1.71 g
molar mass = 342 g
volume of solution = 500 ml
temperature = 300 K
Formula used
number of moles = `"mass of sugar"/"molar mass"`
Molarity = `"number of moles of solute"/"volume of the solution in litres"`
Osmotic pressure ⇒ `pi = CRT`
Solution:
number of moles = `1.71/342`
= 0.005
Molarity (C) = `(0.005 xx 1000)/500`
= 0.01 M
Osmotic Pressure = CRT
`= 0.01 xx 0.083 xx 300`
= 0.249 bar
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Is this statement true or false? Give a reason. - Name the disease caused by taking a lot of salt or salty food, which results in water retention in tissue cells causing puffiness or swelling.
