The atom that is made up of two protons is He. The number of neutrons is also two. The number of electrons matters in the charge. So to make 10 electrons, we add 8 more. hence, 4/2 He 8-.
<span>Selenium (se)
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I
0.5
I hope this helps
Sorry if I’m wrong
6.3 ×

In scientific notation, the numerical value without the exponent of 10 must be within the range from 1 to just below 10 (for example, 9.99...). In this case, 6.3 is already within this range, so we just have to multiply it by 1. To get a multiplier of 1 using base 10, we would have to raise 10 to the zeroth power.