the symbol of Sulphur is, S, N, Si, Cl, the element which is necessary for greening the plant leaves, N, P, S, Fe, The numbeR of negatively charged particles in the a minum atom 2713A equals, 13, 27, The number of neutrons in the nucleus of the atom Of the element39 19X equals, 19, 20, The atomic is written at the upper left side of the element symbol., true, false

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