The atomic number of an element Y is 17. The number of electrons in its ion y^- will be :

45 Why are covalent compounds generally poor conductors of electricity? 46 The atomic number of an element X is 19. The number of electrons in its ion X⁺ will be: 48 The atomic numbers of four elements A, B, C and D are 6, 8, 10 and 12 respectively. The two elements which can react to form ionic bonds (or ionic compound) are: 49 The atomic numbers of four elements P, Q, R and S are 6, 10, 12 and 17 respectively. Which two elements can combine to form a covalent compound ?