19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Thermite a mixture used for welding is:
Anodising can be done by electrolysing dilute H₂SO₄ with aluminium as anode. This results in :
Assertion : PbI₄ is a stable compound. Reason : Iodide stabilizes higher oxidation state.
Assertion : SiF - is known but SiCl - is not. Reason : Size of fluorine is small and its lone pair of electrons interacts with d-orbitals of Si strongly.
Assertion : Between SiCl₄ and CCl₄, only SiCl₄ reacts with water. Reason : SiCl₄ is ionic and CCl₄ is covalent.
Assertion : Pb⁴⁺ compounds are stronger oxidising agents than Sn²⁺ compounds. Reason : The higher oxidation states for the group 14 elements are more stable for the heavier members of the group due to ‘inert pair effe…
Assertion : In water, orthoboric acid behaves as a weak monobasic acid. Reason : In water, orthoboric acid acts as a proton donor.
Assertion : Boron is p block element. Reason : Last electron entres in p sub shell.
Assertion : Boron always forms covalent bond. Reason : The small size of B³⁺ favours formation of co- valent bond.
Assertion : AlF₃ is soluble in KF but addition of BF₃ brings its precipitation. Reason BF₃ is more acidic than AlF₃.
Assertion : BF₃ is a weaker Lewis acid than BCl₃. Reason : BF₃ molecule is stabilized to a greater extent than BCl₃ by B—F p-bonding.
Assertion : Al(OH)₃ is amphoteric in nature. Reason : Al—O and O—H bonds can be broken with equal ease in Al (OH)₃.
When an inorganic compound (X) having 3C—2e as well as 2c—2e bonds reacts with ammonia gas at a cer- tain temperature, gives a compound (Y), isostructural with benzene. Compound (X) with ammonia at a high temperature …
Anodised aluminium is :
A metal X reacts with aqueous NaOH solution to form Y and a highly inflammable gas. Solution Y is heated and CO₂ is poured through it. Z precipitates out and Na₂CO₃ is formed. Z on heating gives Al₂O₃, Identify X, Y a…
The reaction which is not involved in thermite process: (a) 3Mn O 8Al 9Mn 4Al O + ¾¾® + (b) Cr O 2Al 2Cr Al O + ¾¾® + (c) 2Fe Al O Fe O 2Al + ¾¾® + (d) B O 2Al 2B Al O + ¾¾® +
Match the column I with column II and mark the appropriate choice. Column I Column II (A) Galena (i) Abrasive (B) Diamond (ii) Metal carbonyls (C) Carbon monoxide (iii) Hydrides of Si (D) Silanes (iv) An ore of lead
The blue coloured mineral ‘Lapis Lazuli’ which is used as a semi-precious stone is a mineral of the following class:
Which of the following is not matched correctly with its use ?
Compound (B) is:
Compound (A) is:
Aluminium becomes passive in:
Which one of the following metals cannot be extracted by using Al as a reducing agent?
Thermite a mixture used for welding is:
Anodising can be done by electrolysing dilute H₂SO₄ with aluminium as anode. This results in :