What is the chemical compound?
The atomic number tells us the number of protons and electrons.
The atomic mass tells us the weight of the nucleus, which is the amount of protons and neutrons

Here's the balanced equation for given Double displacement reaction ~

The products fored are : Lead Iodide ( PbI2 ) and Potassium Nitrate ( KNO3 )
Answer:
O During photosynthesis, plants take in carbon dioxide from the air.
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
Learn more about parts per billion:brainly.com/question/9179966
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