Simple and Compound Interest Formulas with Questions
Interest is one of the most significant ideas in maths and financial calculations. It is very common in banking, loan applications, investments, saving account and competitive exams. Simple Interest and Compound Interest make it easier to find out how much more is earned and/or paid on a principal during the period of time. These Interest … Read more
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Student Discussion
((w1/M1)/(w1/M1)+(w2/M2))
if vapour pressure of pure liquid is = Po
80 % of pure liquid Ps= 80×Po/100 = 0.8Po
Ps =Po × Xsolute
mass of solute = x gram
mass of solvent = 114g
Molar mass of solute= 40 g/mol
Molar mass of solvent (octane C8H18) = 114g/mol
Number of moles of solute = x/40 = 0.025x
Number of moles of solvent = 114/114= 1 moles
Mole fraction of solvent = 1/(1+0.025x) 0.8Po=Po×1/(1+0.025x)
Cross multiply we get (1+0.025x))0.8Po= Po
Divide by 0.8 Po we get 1+0.025x = 1.25 Subtract 1 both side we get 0.025x = 0.25 Now divide by 0.025
we get
x = 10g
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