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OCR chemistry...please help Watch

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    Okay, I am trying my best to achieve an A or A* grade in ocr chemistry gcse, and I think I can do it, if I learn how to do the hard equations in C5. A question I just attempted (and epically failed at..) was this one:

    KOH + HNO3 -> KNO3 + H2O

    The concentration of potassiumhydroxide solution is 0.100mol/dm3

    Calculate thenumber of moles in 25.0com3 of potassium hydroxide solution
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    Hey! First of all, you must convert the cm3 used in the volume into dm3, which you do by dividing it by 1000.

    So the volume is 25.00/1000 = 0.025 dm3.

    Then, to get the number of moles of solution, multiply the volume (dm3) by the concentration.

    0.025 * 0.1 = 0.0025 mol

 
 
 
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