Chemistry

posted by .

A student heats 5.128g of the sodium carbonate/sodium bicarbonate mixture to a constant mass of 4.256g. Determine the mass of sodium bicarbonate present in the mixture.

  • Chemistry -

    I don't know if this is the right solution or not because you didn't list the temperature.
    Heating to about 270 C converts NaHCO3 to Na2CO3 quantitatively as follows:
    2NaHCO3 ==> Na2CO3 + H2O + CO2

    If heated to a higher temperature, Na2CO3 loses all of the CO2 to form Na2O and I don't think the problem has a solution for that scenario. So I will assume you are talking about the first reaction above.
    Here is what I would do.
    Subtract the two masses and that gives you 0.872 as the loss in weight and that is due to CO2 + H2O. You don't know how much of each you have but you can calculate it.
    Let x = g H2O
    and y = g CO2
    You know x + y = 0.872 grams.
    That's one equation in two unknowns.
    The second one is that you can tell from the equation that moles CO2 and moles H2O are the same (they are equal).
    So
    (x/molar mass H2O) = (y/molar mass CO2)
    That's the second equation.
    Solve these to equations for x and y to determine grams H2O and grams CO2.
    Then choose either one, and convert g of what you chose to moles, convert moles of the product to moles NaHCO3, then convert moles NaHCO3 to grams NaHCO3. That's the answer you are looking for. Good problem.

  • Chemistry -

    Awesome. Thanks!

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    A 3.23 gram sample of a sodium bicarbonate mixture was reacted with excess acid. 48.52 mL of the evolved gas was collected over water at 0.930 arm and 23.0 degrees Celsius. What is the percentage of sodium bicarbonate in the original …
  2. Chemistry

    A 3.23 gram sample of a sodium bicarbonate mixture was reacted with excess acid. 48.52 mL of the evolved gas was collected of the water at .930 atm. and 23.0 degrees C. What is the percentage of sodium bicarbonate in the original mixture?
  3. chemistry

    Write the balanced chemical equation for the reaction of sodium bicarbonate with aqueous acetic acid to produce carbon dioxide, water, and sodium acetate. Follow the example set by the sodium bicarbonate.
  4. Chemistry

    The most abundant cation in seawater is the sodium ion. The evaporation of seawater gives a mixture of ionic compounds containing sodium combined with chloride, sulfate, carbonate, bicarbonate, bromide, fluoride, and tetrahydroxybrate. …
  5. Chemistry

    Which of the following is the most effective buffer system for a pH value of 7.45?
  6. Chemistry

    1. Consider a 1.00g unknown sample that contains 62.0% sodium carbonate and 38.0% sodium bicarbonate, NaHCO3, by mass. When this sample is dissolved in water, how many mL of 0.200M HCl will be required to convert all of the carbonate …
  7. chemistry Please who helps me stpe by step

    2gm of mixture hydrated sodium carbonate na2c03 /OH20 and sodium bicarbonate was dissolved in water and made up to 250cc. 25cc of this solution was titrated, using methyl orange as indicator and 22.5cc of 0.087N hcl were required for …
  8. Chemistry pls clearly step step for me

    2gm of mixture hydrated sodium carbonate and sodium bicarbonate was dissolved in water and made up to 250cc. 25cc of this solution was titrated using methyl orange as indicator and 22.5cc of 0.087N hcl were required for naturalization. …
  9. Chemistry

    A weighed amount of sodium chloride is completely dissolved in a measured volume of 4.00 M ammonia solution at ice temperature, and carbon dioxide is bubbled in. Assume that sodium bicarbonate is formed until the limiting reagent is …
  10. Chem

    A mixture of 5.00 g of sodium carbonate, Na2CO3 and sodium hydrogen carbonate, NaHCO3 is heated. The loss in mass is 0.31 g. Sodium carbonate does not decompose on heating. Calculate the percentage by mass of sodium carbonate in the …

More Similar Questions