std 9 gujarati ch.16 kudarati swadhyay solution || dhoran 9 gujarati ch.16 swadhyay solution || ધોરણ 9 ગુજરાતી પાઠ 16 કુદરતી સ્વાધ્યાય સોલ્યુશન || std 9 gujarat board || std 9 gujarati

Find solution(s) of equation 64(9^(x))-84(12^x)+27(16^x)=0

Which of the following is a solution of the equation 2x-y=16 ? (A) (8,-1) (B) (5,-5) (C ) (6,1) (D) (9,2)

Calculate the molarity (M) and molality (m) of 16% aqueous methanol (CH_(3) OH) solution by volume. Density of solution = 0.9 g mL^(-1) .

Two vessels contain equal quantities of 40% alcohol. Sachin changed the concentration of the first vessel to 50%' by. Adding extra quantity of pure alcohol. Vivek changed the concentration of the second vessel to 50% replacing a certain quantity of the solution with pure alcohol. By what percentage is the quantity of alcohol added by Sachin more/less than that replaced by Vivek? 11 1/9% b. 11 1/9% c. 16 2/3% d. 20 % more

Two solution A and B, each of 80L was made by dissolving 4 gm NaOH and 9.8gm of H_2SO_4 in water respectively. The pH of the resultant solution obtained by mixing 40L of solution A and 20L solution B is….. [Atomic mass H = 1, O = 16, Na = 23 S = 32]

The pKa of the carboxyl group in an amino acid valine, (CH_3)_2 CHCH(NH_2)(COOH) is 2.31 and the pKa for amino group of the same amino acid is 9.69. Compute the isolectric point (pI) for valine and draw the structure of this amino acid when the pH of the solution equals top 1. Also draw the structures of valine that predominate at pH =2 and pOH=2.

The dissociation of weak electrolyte (a weak base or weak acid) id expressed in terms of Ostwald dilution law. An acid is a substance which furnishes a proton or accepts an electron pair whereas a base is proton acceptor or electron pair donor. Storonger is the acid weaker is its conjugate base. The dissociation constants of an acid (K_(a)) and its conjugate base are related by (K_(w)=K_(a)xxK_(b) , where K_(w) is ionic prodcut of water equal to 10-14 at 25^(@) C. The numerical value of K_(w) however increases with temperature. In a solution of an acid or base [H^(+)][OH^(-)]=10^(14) .Thus, the [H^(+)] in a solution is expressed as : [H^(+)]=10^(-pH) and pH+pOH=14 . Buffer solutions are the solutions which do not show appreciable change in the pH on addition of small amount of acid or base. Which of the follwoing statement are true? (P) CIO_(4)^(-) is weaker base than CIO_(3)^(-) (Q) The degree of dissociation of water at 25^(@)C is 1.8xx10^(-9) (R)The equilibrium constant for dissociation of H_(2)O is 1.8xx10^(-16) (S) PO_(4)^(3-) is conjugate acid of HPO_(4)^(2-)