Noble gases.
group 18. elements that are all unreactive .
fixed naming!
Answer:
A rule of thumb is that 1.5 lbs. of baking soda per 10,000 gallons of water will raise alkalinity by about 10 ppm. If your pool's pH is tested below 7.2, add 3-4 pounds of baking soda. If you're new to adding pool chemicals, start by adding only one-half or three-fourths of the recommended amount.
Is this a multiple choice?
Explanation:
The idea here is that you need to use the Periodic Table of elements to find the mass number of the most common isotope of phosphorus, P.
