Std 6 social science chapter 17 jivan nirvah || dhoran 6 samajik vigyan ch.17 swadhyay solution || ધોરણ 6 સામાજિક વિજ્ઞાન પાઠ.17 જીવન નિર્વાહ સ્વાધ્યાય સોલ્યુશન

Chapter 17 Detailed Explanation Part 6

1.22 g of benzoic acid is dissolved in 100 g of acetone and 100 g of acetone seperately. Boiling point of the solution in acetone increases by 0.17^(@) C, while that of solution, in benzene increases by 0.13^(@) C , K_(b) for acetone and benzene is 1.7 K kg mol^(-1) and 2.6 K kg mol^(-1) . Find molecular weight of benzoic acid in two cases. Hence, find their sum.

Two buffer solutions A and B each made with benzoic acid and sodium benzoate differ in their pH by two units. A has salt : acid a:b. B has salt : acid =b:a. If agtb , then the value of a:b is a. 3.17" "b.10.0" "c.3.0" "d. 6.0

Jasmine is a postgraduate in Computer Science passed in first class with 62% marks. She had scored 81% marks in HSC. Her date of birth is 17.6.1979.

Addition of non-volatile solute to a solvent always inceases the colligative properties such as osmotic pressure, DeltaP, DeltaT_(b) and DeltaT_(f) . All these colligative properties are direactly propertional to molality if solutions are dilute. The increase in colligative properties on addition of non-volatile solute is due to incease in number of solute particles. For different aqueous solutions of 0.1 N NaCl, 0.1 N urea, 0.1 N Na_(2)SO_(4) and 0.1 N Na_(3)PO_(4) solution at 27^(@)C , the correct statement are : 1g mixture of glucose and urea present in 250 mL aqueous solution shows an osmotic pressure of 0.74 atm at 27^(@) C . Assuming solution to be dilture, which are correct ? (P) Percentage of urea in solute mixture is 17.6 (Q) Relative lowering in vapour pressure of this solutions is 5.41 xx 10^(-4) . (R) The solution will boil at 100.015^(@)C , if K_(b) of water is 0.5 K "molality"^(-1) (S) If glucose is replaced by same amount of sucrose, the solution will show higher osmotic pressure at 27^(@)C (T) If glucose is repalced by same amount of NaCl , the solution will show lower osmotic pressure at 27^(@)C .

An aqueous solution of sucrose ( C_(12)H_(22)O_(11) ) having a concentration of 34.2gram/ litra has an osmotic pressure of 2.38 atmospheres at 17^(@) C. For an aqurous solution of glucose ( C_(6)H_(12)O_(6) ) to be isotonic with this solution , its concentration should be :

1.22 g of benzoic acid is dissolved in acetone and benzene separately. Boiling point of mixture with acetone increase by 0.17^(@)C and boiling point of mixture with benzene increases by 0.13^(@)C . K_(b) ("acetone")=1.7 K kg "mol"^(-1) , Mass of acetone = 100 g , K_(b) ("benzene")=2.6 k Kg mol^(-1) , Mass of benzene = 100 g , Find molecular weight of benzoic acid in acetone and in benzene solution. Justify your answer with structure.