Specification Point 2.35:
Understand Acids and Bases in terms of Proton transfer

Acids and Bases (Alkalis)

*Acids:

  • When acids react, they will lose electrons to form positive hydrogen ions (H+).
  • These H+ Ions makes the aqueous solution acidic.

    Example: Hydrochloric Acid

HCl (aq)   →    H+ (aq)    +    Cl (aq)

*Bases (Alkalis):

  • When Alkalis react, they will gain electrons to form negative hydroxide ions ( OH).
  • These OH Ions makes the aqueous solution an alkali.

    Example: Sodium Hydroxide

NaOH (aq)   →    Na+ (aq)    +    OH (aq)

Specification Point 2.36:
Understand that an Acid is a Proton Donor and a Base is a Proton Acceptor

Acids and Bases (Alkalis)

Acids and Bases in Transfer of Protons, CIE IGCSE Chemistry

The role of Acids and Bases in the transfer of Protons

*Acids:

  • Acids are a proton donor as they will react to lose electrons to form positive H+ ions
  • These H+ ions makes the aqueous solution acidic

*Bases (Alkalis):

  • Bases (alkalis) are proton acceptors as they will react to gain electrons to form negative OH ions
  • These OH ions makes the aqueous solution acidic

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Author: Jamie

Jamie got a First class degree in Chemistry from Oxford University before going on to teach chemistry full time as a professional tutor. He’s put together these handy revision notes to match the Edexcel IGCSE Chemistry specification so you can learn exactly what you need to know for your exams.