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vova2212 [387]
3 years ago
5

What are periods on the periodic table? How many are there?

Chemistry
1 answer:
Brums [2.3K]3 years ago
8 0
A period is a horizontal row of the periodic table. There are seven periods in the periodic table, with each one beginning at the far left. A new period begins when a new principal energy level begins filling with electrons. Period 1 has only two elements (hydrogen and helium), while periods 2 and 3 have 8 elements.
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What color do you get if you mix red and blue light?
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Purple light.

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1400KJ/mol⁻¹

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7 0
3 years ago
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4 0
3 years ago
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