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How do pH values change when weak acids are neutralised? Watch

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    Please give examples of the weak acid and also the website you found the info on (if used)? I've literally been trawling the internet since yesterday and found 1 sort of ok-ish answer, it's for my chem CA resit and i really need some information to write up on.
    Thank you!
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    When you neutralise any acid, you must be adding a base (such as ammonia - weak base) so the pH will increase - becoming more basic. If you add a strong base (sodium hydroxide) to a strong acid (hydrochloric acid) then the pH will start of low and then will end up high.
    If you add a weak base (ammonia) to a strong acid then the pH will start off low and end up at around 9-10.
    If you use weak acids then the pH will start off higher - at around 3-5 - but will end up the same as if you used a strong acid.
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    (Original post by B_9710)
    When you neutralise any acid, you must be adding a base (such as ammonia - weak base) so the pH will increase - becoming more basic. If you add a strong base (sodium hydroxide) to a strong acid (hydrochloric acid) then the pH will start of low and then will end up high.
    If you add a weak base (ammonia) to a strong acid then the pH will start off low and end up at around 9-10.
    If you use weak acids then the pH will start off higher - at around 3-5 - but will end up the same as if you used a strong acid.
    THANK YOU SO MUCH - but do you have a website that says this? I wish i could reference you but apparently answer sites are unreliable sources...
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    (Original post by tinawu)
    THANK YOU SO MUCH - but do you have a website that says this? I wish i could reference you but apparently answer sites are unreliable sources...
    To be honest for all this information just go to chemguide - search it on google - it is an A-level website but it goes through (everything) - there are pages about acid base reactions that you can learn from and so you can also reference it aswell.
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    (Original post by B_9710)
    To be honest for all this information just go to chemguide - search it on google - it is an A-level website but it goes through (everything) - there are pages about acid base reactions that you can learn from and so you can also reference it aswell.
    Is adding a base the only way to neutralise an acid? and also, is an alkali a base?
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    (Original post by tinawu)
    Is adding a base the only way to neutralise an acid? and also, is an alkali a base?
    Yes the only way to neutralise an acid is to add a base.
    An alkalai is a base that is soluble in water. All alkalais are bases, but not all bases are alkalais.
 
 
 
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