Chemistry Kb question need to clarify something

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the pKb for methylamine is 3.36, what is the Kb for methylamine?

pKa+pKb= 14.00

Kb= 10^-pKb = 4.4x10^-4 is the answer

but HOW?? what is punched into the calculator to get 4.4 x 10^-4??

  • Chemistry Kb question need to clarify something -

    pKb = 3.36
    pKb = -log Kb
    3.36 = -logKb
    -3.36 = log Kb
    Punch in 3.36 and hit the change sign button OR punch in -3.36 directly, then hit the 10^x key. That will return 4.36515E-4 which rounds to 4.36E-4.

  • Chemistry Kb question need to clarify something -

    -3.36(log button or 10^x button)= syntax error ??

  • Chemistry Kb question need to clarify something -

    the key sequence will depend on the type of calculator that you have. If it is a VPAM or similar (like a Casio FX-83) then the sequence is something like

    <shift><10^><-><3><.><3><6><=>

    and the display will show

    0.0004365

    (depending on how the display is set up).

    The exact key sequence will depend on the model of calculator you have.

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