Answer:
Those with 3 protons and 3 neutrons are known as the isotope lithium-6. Those with 3 protons and 4 neutrons are known as the isotope lithium-7.
Explanation:
In a polar covalent bond, the distribution of common electrons are not shared evenly due to a greater positive charge from one atom's nucleus.Oct 30, 2016
Answer:

Explanation:
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In this case, given the masses of copper, zinc and lead, it is possible to compute the moles via their atomic masses first:

Now, we compute the atomic percentages as shown below:

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