2.which of the following solution is a weak electrolyte?
A.0.1M glucose solution
B.2M propanoic acid
C.0.5M NH4Cl solution
D.0.2M Na2CO3 solution
我想知點解b岩?
3.when a coin containing 92% silver and 8% copper is warmed with excess conc.nitric acid,it form?
A.clourless solution
B.pale blue solution
C.colourless solution with some undissole copper
D.pale blue solution with some undissole silver
我想知點解係b唔係a?
4.If gaseous hydrogen chloride is bubbled into fixed volume of dilute hydrochloric acid solution,which of the following are true?
(1)pH value of solution increase
(2)mass of sodium hydroxide required for complete neutralization of solution increase
(3)the conductivity of solution increase
點解2,3岩?但係第1個就唔岩?
更新1:
仲有呀,唔好意思 An aqueous solution of ethanoic acid has a pH value of 4.Which of the following substance when added to this solution,would increase its pH vlaue? (1)solid calcium carbonate (2)solid NaCl (3)aqueous ammonia (4)dilute sulphric acid A.1,3 B.1,4 C.2,3 D.2,4 我想知點解1岩但係2唔岩?