13 atoms are in the chemical formula AI(PO4)3
hope that helps :-)
Charles' law (also known as the law of volumes) is an experimental gas law that describes how gases tend to expand when heated.
Answer: Which Group 1A elements are less dense than pure water at 4 degrees C? Li Na K. How does density vary with temperature? Temperature up, density down.
Explanation:
This question can be easily confused with. During the early times, organic compound are directly associated with living beings, people, plants and animals. That is somewhat true. The definition of organic compounds are compounds that contain carbon. So, it is true that most of the compounds in our body are organic. But you may confuse it to the abundance of elements in the body, which is oxygen. However, the most abundant element, besides carbon, in organic compounds is Hydrogen. You will notice this obviously in the organic compounds like alkanes, alkenes, alkynes, carbohydrates, lipids, hormones and proteins. Their general chemical formula usually involves Carbon and Hydrogen.
The mass of ammonium chloride that must be added is : ( A ) 4.7 g
<u>Given data :</u>
Volume of water ( V ) = 250 mL = 0.25 L
pH of solution = 4.85
Kb = 1.8 * 10⁻⁵
Kw = 10⁻¹⁴
Given that the dissolution of NH₄Cl gives NH₄⁺⁺ and Cl⁻ ions the equation is written as :
NH₄CI + H₂O ⇄ NH₃ + H₃O⁺
where conc of H₃O⁺
[ H₃O⁺ ] =
and Ka = Kw / Kb
∴ Ka = 5.56 * 10⁻¹⁰
Next step : Determine the concentration of H₃O⁺ in the solution
pH = - log [ H₃O⁺ ] = 4.85
∴ [ H₃O⁺ ] in the solution = 1.14125 * 10⁻⁵
Next step : Determine the concentration of NH₄CI in the solution
C = [ H₃O⁺ ]² / Ka
= ( 1.14125 * 10⁻⁵ )² / 5.56 * 10⁻¹⁰
= 0.359 mol / L
Determine the number of moles of NH₄CI in the solution
n = C . V
= 0.359 mol / L * 0.25 L = 0.08979 mole
Final step : determine the mass of ammonium chloride that must be added to 250 mL
mass = n * molar mass
= 0.08979 * 53.5 g/mol
= 4.80 g ≈ 4.7 grams
Therefore we can conclude that the mass of ammonium chloride that must be added is 4.7 g
Learn more about ammonium chloride : brainly.com/question/13050932