I would say because the respiratory system brings in the oxygen for the body and the circulatory system moves it throughout the body with the blood
Make sure the equation is always balanced first. (It is balanced for this question already) 6.022 x 10^23 is Avogadro’s number. In one mole of anything there is always 6.022 x 10^23 molecules, formula units, atoms. For one mol of an element/ compound use molar mass (grams).
Multiply everything on the top = 8.61x10^47
Multiple everything on bottom= 1.20x10^24
Divide top and bottom = 7.15x10^23
Answer: 7.15x10^23 mol SO2
The products will be magnesium phosphate and potassium chloride. You then have to watch a solubility chart to see which one of these is not soluable. In this case it is magnesium phosphate.
Answer is valence electron, they all have total of 2 valence electron.
remember group number = valence electron
I can give you a clue of getting mass. if it is the atomic number is even multiply by 2 but if the atomic number is odd multiply by 2 and add 1
sodium atomic number = 11 so mass = 11*2 +1 = 23
oxygen. atomic number = 8 so mass = 8*2 = 16
carbon atomic number = 6 so mass = 6*2 = 12