19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Assertion : AlF₃ is soluble in KF but addition of BF₃ brings its precipitation. Reason BF₃ is more acidic than AlF₃.
Assertion : Boron always forms covalent bond. Reason : The small size of B³⁺ favours formation of co- valent bond.
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…
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 …
Assertion : Boron is p block element. Reason : Last electron entres in p sub shell.
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.
Anodised aluminium is :
Compound (B) is:
The blue coloured mineral ‘Lapis Lazuli’ which is used as a semi-precious stone is a mineral of the following class:
Compound (A) is:
Which of the following is not matched correctly with its use ?
Thermite a mixture used for welding is:
Which one of the following metals cannot be extracted by using Al as a reducing agent?
Aluminium becomes passive in:
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
Assertion : Between SiCl₄ and CCl₄, only SiCl₄ reacts with water. Reason : SiCl₄ is ionic and CCl₄ is covalent.
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 : 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 : PbI₄ is a stable compound. Reason : Iodide stabilizes higher oxidation state.
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® +
Assertion : In water, orthoboric acid behaves as a weak monobasic acid. Reason : In water, orthoboric acid acts as a proton donor.
Anodising can be done by electrolysing dilute H₂SO₄ with aluminium as anode. This results in :
Which of the following compounds give NH₃ on heating? (I) NH₄NO₃ (II) NH₄NO₂ (III) (NH₄)₂ Cr₂O₇ (IV)(NH₄)₂CO₃ (V) Mg (NH₄) PO₄
Assertion: O₃ has a fishy smell. Reason: It absorbs red part of the visible light.
Assertion: The electronic structure of O₃ is Reason: The following structure is not allowed because the octet around O cannot be expanded.