Acids and Alkalis

• What is the definition of an acid?

  Substance that produces hydrogen ions in aqueous solution.
• What is the definition of a base?

  Substance that can neutralize acids producing a salt and water.
• What is the definition of an alkali?

  Base that is soluble in water.
• How does the pH scale provide information on acids and alkalis?

  • Acids have a pH between 0 and 6
  • Neutral solutions have a pH of 7
  • Alkaline solutions have a pH between 8 and 14
• What is the formula of hydrochloric acid?

  $HCl$
• What does "aq" signify in chemical formulas?

  Aqueous solution, meaning dissolved in water.
• What are two other common acids besides hydrochloric acid?

  Sulfuric acid and nitric acid.
• What ions do acids produce in aqueous solutions?

  Hydrogen ions, $H^+$$.$
• What ions do sulfuric acid and nitric acid produce in aqueous solutions?

  Sulfuric acid produces sulfate ions, $SO_4^{2-};$ nitric acid produces nitrate ions, $NO_3^{-}.$
• What is the neutralization reaction between acids and alkalis?

  • Acids produce hydrogen ions $H^+$
  • Alkalis produce hydroxide ions $OH^{-}$
  • They react to produce water
• What is the difference between bases and alkalis?

  All alkalis are bases, but not all bases are alkalis; alkalis are soluble in water.
• What ions do alkalis produce in aqueous solutions?

  Hydroxide ions, $OH^{-}.$
• How can the pH of a solution be determined?

  • Using a pH probe (electronic measurement)
  • Using universal indicator (color change)
• What color indicates a neutral solution using universal indicator?

  Green.
• What color indicates a very acidic solution using universal indicator?

  Red.
• What is the equation for the neutralization reaction?

  $H^+$$+$$OH^- \rightarrow H_2O$