An antifreeze solution is prepared from 222.6 g of ethylene glycol (C2H6O2) and 200 g of water. Calculate the molality of the solution. If the density of the solution is 1.072 g mL-1, then what shall be the molarity of the solution?
Calculation of Molality :
Mass of ethylene glycol = 222.6 (Given)
Molar mass of ethylene glycol [C2H4(OH)2]
= 2 X 12 + 6 x 1 + 2 x 16
= 62
Therefore moles of ethylene glycol
= 222.6g / 62 gmol-1
= 3.59 mol
Mass of water = 200g (Given)
Therefore molality of the solution is = (moles of ethylene glycol / mass of water) x 1000
= (3.59 / 200) x 1000
= 17.95 m
Calculation of Molarity:
Moles of ethylene glycol = 3.59 mol (already calculated)
Total Mass of solution = 200 + 222.6
= 422.6g
Volume of solution = mass / density volume
= 422.6 / 1.072
= 394.22 ml
now molarity of the solution is = (moles of ethylene glycol / volume of solution) x 1000
= (3.59 / 394.22) x 1000
= 9.11 M
Give simple chemical tests to distinguish between the following pairs of compounds.
(i) Propanal and Propanone
(ii) Acetophenone and Benzophenone
(iii) Phenol and Benzoic acid
(iv) Benzoic acid and Ethyl benzoate
(v) Pentan-2-one and Pentan-3-one
(vi) Benzaldehyde and Acetophenone
(vii) Ethanal and Propanal
A 5% solution (by mass) of cane sugar in water has freezing point of 271 K. Calculate the freezing point of 5% glucose in water if freezing point of pure water is 273.15 K.
How the following conversions can be carried out?
(i) Propene to propan-1-ol
(ii) Ethanol to but-1-yne
(iii) 1-Bromopropane to 2-bromopropane
(iv) Toluene to benzyl alcohol
(v) Benzene to 4-bromonitrobenzene
(vi) Benzyl alcohol to 2-phenylethanoic acid
(vii) Ethanol to propanenitrile
(viii) Aniline to chlorobenzene
(ix) 2-Chlorobutane to 3, 4-dimethylhexane
(x) 2-Methyl-1-propene to 2-chloro-2-methylpropane
(xi) Ethyl chloride to propanoic acid
(xii) But-1-ene to n-butyliodide
(xiii) 2-Chloropropane to 1-propanol
(xiv) Isopropyl alcohol to iodoform
(xv) Chlorobenzene to p-nitrophenol
(xvi) 2-Bromopropane to 1-bromopropane
(xvii) Chloroethane to butane
(xviii) Benzene to diphenyl
(xix) tert-Butyl bromide to isobutyl bromide
(xx) Aniline to phenylisocyanide
A solution of glucose in water is labelled as 10% w/w, what would be the molality and mole fraction of each component in the solution? If the density of solution is 1.2 g mL-1, then what shall be the molarity of the solution?
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The HNH angle value is higher than HPH, HAsH and HSbH angles. Why? [Hint: Can be explained on the basis of sp3 hybridisation in NH3 and only s-p bonding between hydrogen and other elements of the group].
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Write structures of different dihalogen derivatives of propane.
An organic compound contains 69.77% carbon, 11.63% hydrogen and rest oxygen. The molecular mass of the compound is 86. It does not reduce Tollens' reagent but forms an addition compound with sodium hydrogensulphite and give positive iodoform test. On vigorous oxidation it gives ethanoic and propanoic acid. Write the possible structure of the compound.
Nalorphene (C19H21NO3), similar to morphine, is used to combat withdrawal symptoms in narcotic users. Dose of nalorphene generally given is 1.5 mg. Calculate the mass of 1.5 x 10-3m aqueous solution required for the above dose.
Calculate the mass of ascorbic acid (Vitamin C, C6H8O6) to be dissolved in 75 g of acetic acid to lower its melting point by 1.5°C. Kf= 3.9 K kg mol-1.
A 5% solution (by mass) of cane sugar in water has freezing point of 271 K. Calculate the freezing point of 5% glucose in water if freezing point of pure water is 273.15 K.
How are vitamins classified? Name the vitamin responsible for thecoagulation of blood.
Give two examples to show the anomalous behaviour of fluorine.
Y we shouldn't consider the moles of water as we had considered of solute in calculating of total solvent?
Yup it's correct bcs we should always consider the no.of moles....which is more for water here....hence water is solvent...and in las molality can be directly calculated from molarity as molality= 1000 M/1000d-MM' (M = molarity and M'= molar mass of solute)
Ethylene glycol is solute because it has less no. Of moles in the solution in comparison to water.
Why ethylene glycol is solute
Why ethylene glycol is solute here even it is more quantity