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Defines weak bases and describes base ionization equilibrium and how it explains conductivity., Shows how the acid table can be used to identify weak bases and show the trend in their strengths.. Introduces a few weak bases that are not on the table and gives their ionization equations.

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0:01team
0:03acids and bases can be classified as either strong or weak
0:07here will deal with weak bases weekdays is a base
0:11that is less than a hundred percent I nyse: in a quiz solution
0:14form hydroxide ions an example on the weekdays
0:18is the ammonia marquel nh3 ammonia
0:21reacts with water by accepting a proton from water
0:25to form an ammonium I N and hydroxide this process is called the ionization
0:31the weekdays ammonia now look at relative concentrations
0:35when a molecular weak base like ammonia is added to water
0:40and undergoes a small degree are buying is Asian to produce a small number
0:44ammonium
0:45and hydroxide ions
0:47so a solution at NH 3 in water consist mainly of water
0:51and mutual NH three molecules with a small number again age for plus
0:55Ando H minus science
0:57as you might expect a solution ammonia would have low conductivity
1:02due to the low concentration up dissolve diets
1:06and we can summarize by stating that week basis that start out as molecules
1:10like ammonia
1:11are poor conductors or weak electrolytes
1:15way we find weak bases
1:17let's look at the ass a table on the table conjugate base is a ball the acids
1:22are on the right side the conjugate base is on the right
1:26can be divided into three groups
1:29the top five and I ends on the right are spectator and I it
1:34these are the kind you get bases its strong assets
1:37they cannot accept a proton from water to form their kind you get strong acid
1:42this fact is emphasized by the single arrows pointing to the right
1:46the reactions can only proceed to the right strong acid will lose a hundred
1:50percent
1:51ovitz acidic protons to water but the conjugate base has no ability to take a
1:56proton back
1:57from water
1:59you may have noticed that HS up or minus is the conjugate base at the strong acid
2:03sulfuric acid
2:05but it is not called The Spectator I N
2:08by definition spectator ions have no effect on the acidity of solutions
2:13making me they're donating nor accept protons
2:16so they're completely neutral
2:19HS or minus is found here
2:22but it's also found on the left side of the table here
2:26this means that it can act as a weak acid so it is not neutral
2:30therefore it can't be called The Spectator I
2:34three days is on the bottom right we call the strong bases
2:38they are the hydroxide oxide and I might diane's
2:41oxide and my diane's react with water completely to form hydroxide ions
2:46and of course hydroxide ions are already hydroxide ions
2:51species in this red box we call the week basis
2:56they are all capable of accepting a proton from water to form a hydroxide I
3:00N
3:01but because they are weak their reactions with water
3:04do not go to completion
3:06noticed that weak bases are the conjugate base is out weak acids
3:11as we can see by the black bar on the right side at this table
3:15weak bases get stronger as we move down the right side of the table
3:20as we move down the right side of the table and weak bases get stronger
3:24we see that their conjugate acids on the lap get weaker
3:29a general rule is the stronger bases
3:32the weaker its conjugate acid will be
3:35and a stronger acid is the weaker its conjugate base will be
3:40for example biotech acid a child 3
3:43is a relatively strong weak acid
3:46well I'll 3 minus is a very weak base
3:51hydrogen peroxide h2o2 is a very weak acid
3:55well it's kinda get babies HO two-minus
3:58is a relatively strong week based noticed that most to the weak bases on
4:03this table
4:04are science
4:05sources are these weak bases could be soluble salts
4:08for example the salt sodium nitrate Neno to you
4:12could be a source at the weak base nitrate and two-minus
4:17and the weak base bicarbonate 803 minus
4:20could come from the salt sodium bicarbonate which is commonly known as
4:24baking soda
4:26since these are already eye on it solutions of soluble salts a bionic weak
4:31bases
4:32would contain high concentrations %uh buy-ins and would therefore be good
4:36conductors regardless
4:37how strong or weak the bases
4:41we see by looking on the table the HO two-minus
4:44is a much stronger base then I'll 3 minus
4:47so let's compare the conductivities have one mother came out three
4:51src by a three miners with one mother kaho to you
4:55a source at the HO two-minus
4:57let's focus on the key I O three because all potassium salts are soluble
5:02one molar k I'll 3 associates completely to form one molar K plus
5:07and my mother I O three minus