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Deduce the Symbol

1)An Atom of element Q contains the same number of neutrons as are found in an atom of 27 X. An atom of Q also contains 14 protons

Deduce the symbol, include mass and proton number for this atom of element Q.

2) An atom has half as many protons as an atom of Si28 and also has six fewer neutrons than an atom of Si28. Give the symbol, including the mass number and the atomic number, of this atom

Can you also explain how you got each answer please;

(edited 12 years ago)

Reply 1

Kyri

1) The number of protons alone is what decides what an element is. Looking at a periodic table you'll see that an element with 14 protons is silicon. The first part of the statement simply tells you the mass number is 27.

2) Silicon must have 14 protons to be silicon. Half of this is 7, which looking at a periodic table makes it nitrogen. Number of neutrons in 28Si is 28 - 14 = 14. 6 Fewer neutrons than 14 is 8. Therefore you have nitrogen with proton number 7 and mass number 15 (7 protons + 8 neutrons).

Make sense?