The answer is B because isotopes have the same number of protons and neutrons.
Answer:
0.00013
Explanation:
I'm pretty sure. I first subtracted 1.87 from 2. I got 0.13. The conversion from mL to L is 0.001. I multiplied 0.13 and 0.001 and got <u>0.00013 mL.</u>
The element is Magnesium
- It has total 12 electrons
it has electronic configuration
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or
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In valence cell it has 2 electrons and therefore its valency is 2
<span>The correct answers are A, B, and D. The ΔHrxn is equal to the ΔHf when the ΔHf of the reactants is zero, and this can only occur when the reactants are pure elements (not compounds) in their natural phase at ambient temperature.
c) Chlorine's natural phase is gaseous, but since it is a liquid in this reaction, ΔHf ≠ 0.
e) CO is a compound, not a pure element.
f) BaCO3 is a compound, not a pure element.</span>