Chemistry

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I..don't understand any of this:

43. How many moles are in 25.0 grams of potassium? Show your work and round your answer to the appropriate number of significant figures.

Please, please help with this!
Thanks
-MC

  • Chemistry -

    moles = grams/molar mass

  • Chemistry -

    How do I figure out the molar mass?

    -MC

  • Chemistry -

    Look up the atomic mass of each element and add.
    molar mass NO = about 30.
    N = 14 is atomic mass.
    O = 16 is atomic mass.
    total = 30 = molar mass.

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