The base-dissociation constant of ethylamine (c2h5nh2) is 6.4 ??? 10???4 at 25.0 ?? c. the [h ] in a 1.2 ??? 10-2 m solution of ethylamine is ________ m.
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To find the concentration of [�+]
[H+
] in a solution of ethylamine (�2�5��2
C2
H5
NH2
), you can use the base-dissociation constant (��
Kb
) expression:
��=[��−][�2�5��3+][�2�5��2]
Kb
=[C2
H5
NH2
]
[OH−
][C2
H5
NH3
+
]
Since ethylamine is a weak base, you can assume that the concentration of [��−]
[OH−
] is equal to [�2�5��3+]
[C2
H5
NH3
+
] in the equilibrium equation.
��=[��−]2[�2�5��2]
Kb
=[C2
H5
NH2
]
[OH−
]2
Given ��=6.4×10−4
Kb
=6.4×10−4
and [�2�5��2]=1.2×10−2 �
[C2
H5
NH2
]=1.2×10−2
M, you can solve for [��−]
[OH−
]. Once you have [��−]
[OH−
], you can use the relation [�+]×[��−]=1.0×10−14
[H+
]×[OH−
]=1.0×10−14
to find [�+]
[H+
].
[�+]=1.0×10−14[��−]
[H+
]=[OH−
]
1.0×10−14
Please perform the calculations to find the value of [�+]
[H+
].