28. What charges are most commonly observed for mona- tomic ions of the following elements?
(a) selenium
(c) iron
(b) fluorine
(d) nitrogen

(a) selenium

(a)           Se2–

(b) fluorine

(b)           F–

(c) iron

(c)           Fe2+, Fe3+

(d) nitrogen

(d)           N3–

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no, the red giant is the hottest with 2.00.000.000 degrees celsius. while the white dwarf only 25,000 degrees celsius.