Acids, alkalis and the pH scale

• Which ion do acids always form when they dissolve in water?

  Hydrogen ions (H+ ions) – also called protons
• Which ion do alkalis always form when they dissolve in water?

  Hydroxide ions (OH-)
• What is the definition of dissociation?

  When an ionic compound dissolves and splits into its constituent ions
• What ions form when nitric acid dissociates in water?

  H+ and NO3- ions
• What ions form when hydrochloric acid dissociates in water?

  H+ and OH- ions
• What ions form when sulfuric acid dissociates in water?

  2 H+ and SO42- ions
• What are strong acids?

  Acids that fully dissociate into ions when they dissolve in water
• What are weak acids?

  Acids that DO NOT fully dissociate into ions when they dissolve in water
• How would the pH values differ between strong and weak acids of the same concentration?

  strong acids have lower pH values (closer to 0)

  Weak acids have higher pH values (around pH 3 to 6)
• What is the ionic equation for any neutralization reaction? Include state symbols.

  .H+ (aq)     +    OH- (aq)         H2O (l)