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Natali [406]
3 years ago
7

Why was helium absent from mendeleev's original periodic table of 1871?

Chemistry
1 answer:
34kurt3 years ago
6 0
<span>This is because it was not yet discovered during that time. Helium (noble gases) was extremely difficult to discover that time because it does not react with other elements. And now since Mendeleev had based his table on the similar properties of known elements he could not have included Helium in his table.</span>
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HURRYYY!!!!<br> Convert 7.13 x 10^28 atoms of calcium (Ca) to moles of calcium.
puteri [66]

Answer:

<h2>118,438.5 moles</h2>

Explanation:

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From the question we have

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<h3>118,438.5 moles</h3>

Hope this helps you

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