Write the electronic configuration of a positively charged sodium ion (Na+). Atomic number of sodium is 11.
Number of electrons in Na atom = Atomic number = 11 Number of electrons in Na+ ion = 1 1 - 1 = 10 Electronic configuration of Na+ ion: 2,…
Write two characteristics of the canal rays.
(i) The canal rays are deflected by the magnetic fields in a direction opposite to that of the cathode rays. (ii) They consist of positively charged particles.
How do you know that nucleus is very small as compared to the size of atom?
Rutherford observed that when α-particles were bombarded on a very thin foil they bounced back. But the number of a-particles bouncing back got doubled when he doubled the thickness of…
Will 35Cl and 37Cl have different valencies? Justify your answer.
No, 35Cl and 37Cl are isotopes of an element.
An element ‘A’ has valency +3, while another element ‘B’ has valency -2. Give the formula of their compound formed when ‘A’ reacts with ‘B’.
Element 'A' valency +3 (left) Element 'B' valency - 2 (right) Chemical formula = A2B3
Which isotope of hydrogen is present in heavy water?
Among the three isotopes of hydrogen, deuterium ( 2H1) is found in heavy water.
Give two important applications of radioactive isotopes.
(i) An isotope of carbon-12, C14, is used in carbon dating. (ii) U235 is used in the nuclear reactors to generate electricity.