Answer:
im pretty sure you need 15 in all but dont get mad it thats wrong, so you would i think need 3 neutrons
Explanation:
From the calculation, the concentration in parts per billion is 6 ppb.
<h3>What is ppb?</h3>
The term ppb refers to the concentration of a substance in parts per billion. We obtain the ppb using the formula;
Mass of solute/ Mass of solution * 10^9
Now, 1L = 1000cm^3 = 1000 g
The concertation in ppb = 6 * 10^-6 g/1000 g * 10^9
= 6 ppb
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