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## Atomic Structure and Isotopes ### Question 1 * Neutrons = 9, n = 14 - 7 = 9. * Protons = 9, p = 7 * No. of p = Z = Atomic nu. * No. of N = A - Z * Mass no(A) = p + N ### Question 2 If the atomic mass weight of an element is 23 times that of the lightest element and it has 11p, then it conta...

## Atomic Structure and Isotopes ### Question 1 * Neutrons = 9, n = 14 - 7 = 9. * Protons = 9, p = 7 * No. of p = Z = Atomic nu. * No. of N = A - Z * Mass no(A) = p + N ### Question 2 If the atomic mass weight of an element is 23 times that of the lightest element and it has 11p, then it contains 9 neutrons. Let X be the element. * $23 = \frac{A}{1}$ * A = 23 * 1 * 1 * p = 11 * N = 12 ### Question 3 The no. of extra neutrons in tripositive Al ions with A = 27.18 * A = 27 * p = 13 * N = 27 - 13 = 14 * E = 13 - 3 = 10 **Atoms have two charges** > * p-charge (positive charge) = +e > * -ve charge = -e **T30 isotopes & T30 Isobars** * **Same atomic no.** - same no. of protons * **But different mass no.** - same no. of nucleons, mass no. but different no. of protons, ie. 13 or 26. * **Same no. of protons** - but different no. of Neutrons