1/5 + 1/4 =1/x
4x + 5x = 20
9x = 20
x = 2.22 hours Answer
Answer:
The average atomic mass of an element is the sum of the masses of its isotopes, each multiplied by its natural abundance (the decimal associated with percent of atoms of that element that are of a given isotopе). An element does not have an absolute atomic mass.
<em>Hope</em><em> this</em><em> </em><em>helps</em><em> </em><em>:</em><em>)</em>
Answer:
When observing how thallium reacts with the air of the earth's atmosphere, its hardness or resistance resembled sodium, it was not investigated further to classify it correctly
Explanation:
Now it is known that they contain different numbers of valence electrons and that thallium is a heavy metal like lead and that they have similar characteristics except for their melting point where thallium is higher.
Your answer is B. It gets energy from the Sun.
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