Abuffer is prepared by dissolving 0.80 moles of nh3 and 0.80 moles of nh4cl in 1.00 l of aqueous solution. if 0.10 mol of naoh is added to 250 ml of this buffer, what is the ph of the resultant solution?
a.10.54
b.4.27
c.8.78
d.9.73
e.5.22

a. 10.54

Explanation:

reaction is

NH₃ +  NaOH   NH₄Cl + H₂O

0.10 mol NaOH will consume 0.10 mol NH₃ thereby decreasing the initial amount of moles NH₃ and increasing that of NH₄Cl

mol NH₃  = 0.80 - 010 = .70

mol NH₄Cl = 0.80 + .10 = 0.90

pH = pKₐ + log (( NH₃/NH₄Cl))

pH =  9.26 + log (( 0.90 + 0.70)) = 9.26 + 0.11 = 10.54

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.