In a sample of ethyl ethanoate (CH₃COOC₂H₅) the two oxygen atoms have the same number of electrons but different number of neutrons. Which of the following is the correct reason for it?
Is it possible for the atom of an element to have one electron, one proton and no neutron. If so, name the element.
Will ³⁵Cl and ³⁷Cl have different valencies? Justify your answer.
The atomic number of calcium and argon are 20 and 18 respectively, but the mass number of both these elements is 40. What is the name given to such a pair of elements?
Fill in the blanks in the following statements (a) Rutherford's α-particle scattering experiment led to the discovery of the ——— (b) Isotopes have same ———but different———. (c) Neon and chlorine have atomic numbers 10 and 17 respectively. Their valencies will be———and———respectively. (d) The electronic configuration of silicon is ———and that of sulphur is ———.
Characteristics of an Isotope represent: (I) Isotopes have different numbers of neutrons. (II) Isotopes have same number of electrons and protons. (III) Isotopes have different chemical properties. (IV) Isotopes have different physical properties. Which of the following represent the properties of an Isotope?
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