Chemistry
Give one word or a phrase for the following statements:
(i) The chemical bond formed by a shared pair of electrons, each bonding atom contributing one electron to the pair.
(ii) Electrode used as cathode in electrorefining of impure copper.
(iii) The substance prepared by adding other metals to a base metal in appropriate proportions to obtain certain desirable properties.
(iv) The tendency of an atom to attract electrons to itself when combined in a compound.
(v) The reaction in which carboxylic acid reacts with alcohol in the presence of conc. H2SO4 to form a substance having a fruity smell.
Related Questions
(i) Draw the structural formula for each of the following:
- 2,2 dimethyl pentane
- methanol
(ii) Write the IUPAC name for the following compounds:
- acetaldehyde
- acetylene
Fill in the blanks from the choices given in brackets:
(i) The polar covalent compound in gaseous state that does not conduct electricity is ……………
(carbon tetra chloride, ammonia, methane)
(ii) A salt prepared by displacement reaction is ……………
(ferric chloride, ferrous chloride, silver chloride)
(iii) The number of moles in 11gm of nitrogen gas is ……………
(0.39, 0.49, 0.29) [atomic mass of N=14]
(iv) An alkali which completely dissociates into ions is ……………
(ammonium hydroxide, calcium hydroxide, lithium hydroxide)
(v) An alloy used to make statues is ……………
(bronze, brass, fuse metal)
State one relevant reason for each of the following:
(i) Graphite anode is preferred to platinum in the electrolysis of molten lead bromide.
(ii) Soda lime is preferred to sodium hydroxide in the laboratory preparation of methane.
(iii) Hydrated copper sulphate crystals turn white on heating.
(iv) Concentrated nitric acid appears yellow, when it is left for a while in a glass bottle.
(v) Hydrogen chloride gas fumes in moist air.
Calculate:
(i) The amount of each reactant required to produce 750 ml of carbon dioxide, when two volumes of carbon monoxide combine with one volume of oxygen to produce two volumes of carbon dioxide.
2CO + O2 ⟶ 2CO2
(ii) The volume occupied by 80 g of carbon dioxide at STP.
(iii) Calculate the number of molecules in 4.4 gm of CO2.
[Atomic mass of C= 12, O=16]
(iv) State the law associated in question no. (f)(i) above.