chemistry

posted by .

A 2.500 gram sample of hydrate of calcium sulfate loses 0.532 grams of water when heated. Determine the mass percent of water in the hydrate and the formula of the hydrate.

  • chemistry -

    It lost 0.532 g H2O out of a 2.500 g sample.
    %H2O = (mass water lost/mass sample) x 100 = approximately 22 but you need to go through it to do it more exacting than that.

    Now take 100 g sample. That will give you
    22% H2O (or the value you recalculate)
    78% CaSO4 (found by 100%-% water)

    22/molar mass H2O = moles H2O
    78/molar mass CaSO4 = moles CaSO4.

    Now find the ratio of the two numbers in small whole numbers. The easy way to do this is to divide the small number by itself give 1.000 for that. Then divide the other number by the same small number. Round to whole numbers and you have the formula written this way.
    CaSO4.xH2O where x is what you find.

  • chemistry -

    20.92 %

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. chem

    a 2.50g sample of hydrate of calcium sulfate losses 0.523g of water when heated. what is the mass percent of water in the hydrate and the formula for the hydrate difference of the two masses divided by the initial mass. I believe Adam …
  2. chemistry

    In the experiment, a hydrate is heated to form an anhydrate. The masses of the before and after are measured and the percent of the water in the hydrate is calculated. If some of the hydrate spatters out of the crucible and isnt noticed, …
  3. chem

    A 3.48 gram sample of sodium sulfate hydrate lost 1.35 gram of water when heated to constant weight. What is the formula of the hydrate?
  4. chemistry

    A 2.50 g sample of a hydrate of calcium sulphate losses 0.523 g of water when heated. Determine the mass percent of water in the hydrate and the formula of the hydrate.
  5. chemistry

    I need help with this lab. Write the equation for the decomposition of the hydrate, CuSO4*XH2O. Mass of crucible and hydrate: 93.000g Mass of crucible and pure salt: 91.196g I need to calculate the following: 1. mass of water in hydrate …
  6. Chemistry

    I need help with this lab. Write the equation for the decomposition of the hydrate, CuSO4*XH2O. Mass of crucible and hydrate: 93.000g Mass of crucible and pure salt: 91.196g I need to calculate the following: 1. mass of water in hydrate …
  7. chemistry

    If 4.02 grams of a hydrate of magnesium sulfate loses 2.06 grams of water when heated, what is the formula for the hydrate
  8. Chemistry

    Experiment 1 results: mass of crucible 88g mass of hydrate 93g mass of salt 91.196g 1. Calculate the following: a:mass of water in the hydrate sample (g) b:number of moles of water in the sample c:mass of pure salt in the sample (g) …
  9. Chemistry

    7. A student conducts an experiment on a different hydrate. The empty crucible is heated to a constant mass of 24.330. A sample of the unidentified hydrate is placed in the crucible, and the total mass is 31.571 g. The crucible and …
  10. Chemistry

    A hydrate of copper (II) sulfate with formula CuSO4.xH2O has a molar mass of 250.0 g/mol. 2.545 g of hydrate is heated and 63.85% of the residue is found after heating. a) Determine the value of x in the formula of the compound b) …

More Similar Questions