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vazorg [7]
3 years ago
8

What ion will be formed by the selenium atom shown below when it has a stable set of valence electrons?

Chemistry
1 answer:
kirill [66]3 years ago
7 0

Answer:

Se⁻²

Explanation:

Even though the atom is not shown, we can consult the periodic table. Selenium (Se) is in group 6 and period 4, so it has 6 valence electrons. To be stable, the atom must have a noble gas configuration with 8 valence electrons, thus, selenium must gain 2 electrons.

When an atom gain electrons, it is negatively charged, because electrons have a negative charge. So, the ion formed is Se⁻².

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then, we need to get the concentration of [Na2HPO4]:
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