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Oxyacids quiz

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  • What is an oxyacid?
    An oxyacid is a covalent compound containing hydrogen ions bonded to a polyatomic ion that includes oxygen.
  • How do you form nitrous acid from ions?
    Nitrous acid (HNO2) is formed by combining H+ with the nitrite ion (NO2−).
  • What is the formula for sulfurous acid and how is it formed?
    Sulfurous acid (H2SO3) is formed by combining H+ with the sulfite ion (SO3^2−), crisscrossing the numbers.
  • What is the oxyacid strength rule?
    If a neutral oxyacid has two or more oxygen atoms than hydrogen atoms, it is considered a strong acid.
  • How do you determine if HClO3 is a strong or weak oxyacid?
    HClO3 has three oxygens and one hydrogen, so subtracting gives two oxygens remaining, making it a strong acid.
  • Why is HOCN considered a weak oxyacid?
    HOCN has one oxygen and one hydrogen, so there are no oxygens remaining, making it a weak acid.
  • What are the exceptions to the oxyacid strength rule?
    Oxalic acid (H2C2O4) and iodic acid (HIO3) are exceptions; they are weak despite having two more oxygens than hydrogens.
  • Why are oxalic acid and iodic acid exceptions to the strength rule?
    Their central elements, carbon and iodine, have low electronegativities, making them weak acids.
  • How do you compare the strength of two oxyacids with different numbers of remaining oxygens?
    The oxyacid with more remaining oxygens after subtracting hydrogens is stronger.
  • What determines the strength of oxyacids if the number of remaining oxygens is the same?
    The oxyacid with the more electronegative central element is stronger.
  • How does electronegativity affect oxyacid strength?
    Higher electronegativity of the central element increases the acidity of the oxyacid.
  • Between sulfur and selenium, which makes a stronger oxyacid and why?
    Sulfur is more electronegative than selenium, so H2SO3 (sulfurous acid) is more acidic than H2SeO3.
  • What is the key factor in comparing oxyacid strengths?
    The number of remaining oxygens after subtracting hydrogens is the key factor.
  • What is the general method for identifying an oxyacid?
    An oxyacid is identified as an acid with hydrogen bonded to a polyatomic ion containing oxygen.
  • What should you do to determine if an oxyacid is strong or weak?
    Subtract the number of hydrogens from oxygens; if two or more oxygens remain, it's strong unless it's an exception.