Which one of the following is a correct electronic configuration of sodium? (a) 2, 8 (b) 8, 2, 1 (c) 2, 1, 8 (d) 2, 8, 1 Open Answer Β»
Put tick (β ) against correct choice and cross ( x ) against wrong choice in the following question: Number of valence electrons in Clβ ion are: (a) 16 (b) 8 (c) 17 (d) 18 Open Answer Β»
Put tick ( β ) against correct choice and cross ( x ) against wrong choice in the following question: Isotopes of an element have (a) the same physical properties (b) different chemical properties (c) different number of neutrons (d) different atomic numbers Open Answer Β»
Put tick (β ) against correct choice and cross ( x ) against wrong choice in the following question: Rutherfordβs alpha-particle scattering experiment was responsible for the discovery of (a) Atomic nucleus (b) Electron (c) Proton (d) Neutron Open Answer Β»
For the following statements, write T for βTrueβ and F for βFalseβ. (a) J.J. Thomson proposed that the nucleus of an atom contains only nucleons. (b) A neutron is formed by an electron and a proton combining together. Therefore, it is neutral. (c) The mass of an electron is about 1/2000 times that of proton. (d) An isotope of iodine is used for making tincture iodine, which is used as a medicine. Open Answer Β»
Composition of the nuclei of two atomic species X and Y are given as under X Y Protons = 6 6 Neutrons = 6 8 Give the mass numbers of X and Y. What is the relation between the two species? Open Answer Β»
The average atomic mass of a sample of an element X is 16.2 u. What are the percentages of isotopes π8 16 and π8 18 in the sample? Open Answer Β»