1.
Fill in the blanks to complete the following table Symbolz #of protonselectrons neutrons #of |
Charge #of Fe 58 24 36 Sr2+ 16 2 16
Solution
Fe: Iron is the 26th element and its mass number is 58. Hence it has 26 protons and 32 neutrons.
Since the given number of electrons is 2 less than the number of protons, the charge is +2.
Sr2+ : strontium is 38th element with mass 88. Hence the number of protons is 38. Since the
charge is +2, the number of electrons is 36.
As- arsenic is 33rd element with mass number 75. Hence number of protons and electrons are 33
and neutrons = 75-33 = 42. The charge is neutral.
S- sulphur is the16th element with mass number 32. The number of neutrons and protons are 16.
Since the charge is -2, number of electrons = 18.
Symbol Z A protons electrons neutrons charge
Fe2+ 26 58 26 24 32 +2
Sr2+ 38 88 38 36 50 +2
As 33 75 33 33 42 0
S2- 16 32 16 18 16 -2