If a student attempts to identify an unknown compound by methodused in this experiment. She finds that when she heated a sampleweighing 0.4862 g the mass went down appreciably, to 0.3067 g. Whenthe product was converted to chloride, the mass went up, to 0.3382g.
a. Is the sample a carbonate? Give yourreasoning.
b. What are the two compounds that might be theunknown?
c. Write the chemical equation for the overallreaction that would occur when the original compound was convertedto a chloride. If the compound is a hydrogen carbonate, use the sumof Reactions 1 and 2. If the sample is carbonate, use Reaction 2.Write the equation for a sodium salt and the for a potassiumsalt.
d. How many moles of the chloride salt would beproduce from one mole of the original compound?
e. How many grams of the chloride salt would beproduced from one molar mass of the original compound?
Molar masses: NaHCO3 _______g Na2CO3 _______g NaCl_______g
KHCO3 _______g K2CO3 _______g KCl_______g
If a sodium salt, _______g original compound -> _______g chloride
If a potassium salt, _______g original compound -> _______gchloride
f. What is the theoretical mass ratio, mass chloride/mass original compoud?
If she has an Na salt _______:1 if she has a K salt _______:1
g. What was the observed mass ratio,mass chloride/mass original salt?
h. Which compound did she have an unknown?
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