chemistry

posted by .

Based on the balanced equation
2Ba + O2 → 2BaO

calculate the number of BaO formula units formed when 142 Ba atoms and 73 O2 molecules react?

  • chemistry -

    You know it's a limiting reagent problem when both of the starting materials are given. You must determine which is the limiting reagent.
    Two calculations will do it.
    142 Ba x (2 moles BaO/2 moles Ba) = 142 x 1/1 = 142 BaO molecules formed.

    73 O2 x (2 moles BaO/1 moles O2) = 73 x (1/2) = 146 BaO molecules formed.

    Both answers can't be correct; the correct one is ALWAYS the smaller. Therefore Ba is the limiting reagent and 142 BaO molecules (formula units) will be formed. Some of the oxygen will remain unreacted. You can determine how much is left easily.
    142 Ba atoms x (1 mole O2/2 moles BaO) = 142 x (1/2) = 71 molecules O2 used. We had 73 initially; therefore, 73-71 = 2 molecules O2 remain unreacted.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    Based on the balanced equation Al2S3 + 6H2O → 2Al(OH)3 + 3H2S calculate the number of excess reagent units remaining when 4 Al2S3 formula units and 30 H2O molecules react?
  2. chemistry

    Based on the balanced equation 2I2O5 + 10NO → 5N2O4 + 2I2 calculate the number of excess reagent units remaining when 188 I2O5 molecules and 850 NO molecules react?
  3. chemistry

    Based on the balanced equation 2Al + 6HCl → 2AlCl3 + 3H2 calculate the number of excess reagent units remaining when 140 Al atoms and 402 HCl molecules react?
  4. Chemistry

    Based on the balanced equation 2NBr3 + 3NaOH → N2 + 3NaBr + 3HOBr calculate the number of NaBr formula units formed when 126 NBr3 molecules and 192 NaOH formula units react?
  5. Chemistry

    Based on the balanced equation 2Ba + O2 → 2BaO calculate the number of BaO formula units formed when 54 Ba atoms and 21 O2 molecules react?
  6. Chemistry

    Based on the balanced equation 2NBr3 + 3NaOH → N2 + 3NaBr + 3HOBr calculate the number of of excess reagent units remaining when 116 NBr3 molecules and 180 NaOH formula units react?
  7. College Chem

    Based on the balanced equation 4Na + O2 → 2Na2O calculate the number of Na2O formula units formed when 60 Na atoms and 10 O2 molecules react?
  8. College Chem

    Based on the balanced equation 4Na + O2 → 2Na2O calculate the number of Na2O formula units formed when 60 Na atoms and 10 O2 molecules react?
  9. Reposting Chemistry College

    Based on the balanced equation 4Na + O2 → 2Na2O calculate the number of Na2O formula units formed when 60 Na atoms and 10 O2 molecules react?
  10. chemistry

    The value of ΔH° for the reaction below is -1107 kJ: 2Ba (s) + O2(g) → 2BaO (s) How many kJ of heat are released when 5.75 g of Ba (s) reacts completely with oxygen to form BaO (s)?

More Similar Questions