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Element A has mass number 40 and 21 neutrons
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asked
Jun 21, 2021
in
Chemistry Form 2
by
anony mous
Element A has mass number 40 and 21 neutrons
Write the electron arrangement of element A.
Give the formula of the compound formed when element A reacts with Sulphur. (S = 16.0)
structure of the atom
periodic table
electron arrangement
formula
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Jun 21, 2021
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anony mous
No. of electrons; 40−21=19
Electron arrangement; 2.8.8.1 or
2 8 8 1 or 2,8,8,1, or 2:8:8:1
A
2
S or SA
2
or K
2
S or SK
2
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