Some Basic Concepts of Chemistry Questions (NEET, JEE Main) – Test 5 1

Suppose the elements X and Y combine to form two compounds XY₂ and X₃Y₂. When 0.1 mole of XY₂ weighs 10 g and 0.05 mole of X₃Y₂ weighs 9 g, the atomic weights of X and Y are [NEET 2016]

If Avogadro number N_A, is changed from 6.022 × 10²³ mol^–1 to 6.022 × 10²⁰ mol^–1, this would change [AIPMT 2015]

The number of water molecules is maximum in [AIPMT 2015]

Concentrated aqueous sulphuric acid is 98% H₂SO₄ by mass and has a density of 1.80 g.mL^–1. Volume of acid required to make 1 litre of 0.1 M H₂SO₄ solution is: [CBSE AIPMT Preliminary 2007]

The mass of carbon anode consumed (giving only carbon dioxide) in the production of 270 kg of aluminium metal from bauxite by the Hall process is:

(Atomic mass : Al = 27) [CBSE AIPMT Preliminary 2005]