The formula C2H4 can be classified as both a molecular formula
and an empirical formula. The answer is number 4.
H :) (I tried sorry if im wrong)
Consequently, the ion with the greatest nuclear charge (Al 3 +) is the smallest, and the ion with the smallest nuclear charge (N 3−) is the largest. The neon atom in this isoelectronic series is not listed in Table 2.8.3, because neon forms no covalent or ionic compounds and hence its radius is difficult to measure.
In physics, electromagnetic radiation refers to the waves of the electromagnetic field, propagating through space, carrying electromagnetic radiant energy. It includes radio waves, microwaves, infrared, light, ultraviolet, X-rays, and gamma rays
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