Answer:
Element: H (hydrogen)
Compound: H2O (water)
Explanation: An element is made up of a singular atom while a compound is made up of 2 or more
<u>Answer:</u>
The correct answer option is a. Selenium (Se).
<u>Explanation:</u>
From the given answer options, Selenium (Se) is the only element which is a non metal.
It has the atomic number 34 with atomic weight 78.96. It is a member of the sulfur group of the non metallic elements and falls in period 4 of the Periodic table.
Selenium has non metallic properties which are intermediate between the elements that lie above and below it in the Periodic table.
The mass number goes on top, and the atomic number goes on bottom.
Therefore, the answer is C:
40
K
19
The (( mole calcium ))s are simplified so the answer is based on the number of calcium atoms.
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And we're done.
Thanks for watching buddy good luck.
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