Choose appropriate words from the following list & fill in the blanks I to VI below: [5] (Anions, anode, cathode, cations, electrode, electrolyte, nickel, voltameter, dilute sulphuric acid) To electroplate an article with nickel requires an (i) ------------ which must be a solution containing (ii) ------------ions. The article to be plated is placed as the (iii) ----------------- of the cell in which the plating is carried out. The (iv) ---------- of the cell is made from pure nickel. The ions that are attracted to the negative electrode & discharged are called (v) ----------.
Answers
Answer:
By crumpling the paper into a ball, the volume of the object decreases but the mass remains the same. Hence its density increases.
As air applies some resistance on falling sheet of paper as well as crumpled ball but the resistance to the motion of crumpled ball through the air decreases that makes it to fall faster than the sheet of paper.
Solution:-
(a) Powdered sodium chloride (common salt) does not conduct an electric current, but it does so when dissolved in water or when melted.
(b) Molten lead bromide conducts electricity .It is called an electrolyte. It is composed of lead ions and bromide ions. The lead ions are positively charged and are called cations. The bromide ions are negatively charged and are called anions.
(c) Substances which conduct electricity in the solid state are generally metals.
(d) The electron releasing tendency of zinc is more than that of copper.
(e) A solution of HCl gas in water conducts electricity because it ionizes , but a solution of HCl gas in toluene does not conduct an electric current because it does not ionize in toluene.