<span>The behavior, or reactivity, of elements in a group, or family will behave similarly because they have the same numbers of valence electrons. An example might be the alkali metals (with the exception of hydrogen, H, which is a gas) which form +1 ions in their compounds, have a relatively low melting point, and react violently with water. Other groups of atoms also show similar properties although different from the alkali metals. This type of behavior is one of the things that helps us categorize the elements into the periodic table of the elements. Mendeleev noticed similarities in the behavior of certain elements that originally allowed him to place them into families and develop that periodic chart</span>
I think it would be a law
The balanced equation for the reaction between Ba(OH)₂ and HCl is as follows;
Ba(OH)₂ + 2HCl ---> BaCl₂ + 2H₂O
stoichiometry of Ba(OH)₂ to HCl is 1:2
the number of HCl moles that have reacted - 0.2452 mol/L x (20.00 x 10⁻³ L)
number of HCl moles reacted = 0.004904 mol
2 mol of HCl reacts with 1 mol of Ba(OH)₂
therefore 0.004904 mol of HCl reacts with - 1/2 x 0.004904 mol of Ba(OH)₂
number of Ba(OH)₂ moles in 18.15 mL - 0.002452 mol
Therefore number of Ba(OH)₂ moles in 1000 mL- 0.002452 mol /(18.15 x 10⁻³ L)
molarity of Ba(OH)₂ is = 0.1351 M
Protons, it was once organized by atomic mass but organizing by protons turned out to be better