Boron is non metal while other elements of IIIA group are metals. This is because______________?
(A) it has small size
(B) it has high nuclear charge
(C) it forms molecular addition compounds
(D) all of the above
Boric acid cannot be used__________________?
(A) As antiseptic in medicine
(B) For washing eyes
(C) In soda bottles
(D) For enamel and glazes
Identify the correct statement regarding CO_______________?
(A) it combines with H2O to form carbonic acid
(B) it reacts with red blood cells of haemoglobin
(C) it is powerful oxidizing agent
(D) it is used to prepare aerated drinks
CO2 is gas while SiO2 is solid at room temperature?
(A) carbon is non-metal while silicon is semi-metal
(B) CO2 is an independent molecule while SiO2 has network covalent structure
(C) CO2 forms multiple bond while silicon does not form multiple bonds
(D) Silicon has all sigma bonds
Which of the following is not a use of silicon ?
(A) Lubricants
(B) Hydraulic brakes
(C) Antifreeze
(D) Water repellent
Aqueous solution of borax above 62°C gives crystals of________________?
(A) Na2B4O7.4H2O
(B) Na2B4O7.5H2O
(C) Na2B4O7.2H2O
(D) Na2B4O7.10H2O
The process of aluminium extraction is called__________________?
(A) Hall process
(B) Thermite process
(C) Haber process
(D) Contact process