Our labs this term were intended to highlight concepts discussed in the book and

Question

Our labs this term were intended to highlight concepts discussed in the book and the course recordings. They used simple compounds that could easily be obtained at home.

a) What safety precautions should be taken when doing these experiments at home? None is not an acceptable answer though virtually any other well-reasoned argument may be accepted.        

b) Considering the experiment measuring the pressure of the gases in the balloon. Recall that you used vinegar and baking soda for that experiment and one of these was a limiting reactant. We measured the circumference of the balloon, using string, and approximated the balloon as a sphere to calculate the volume. I had you research the barometric pressure on the day of the experiment. Now, I want you to give me a complete discussion of the experiment by answering the following questions. Be sure to give complete answers.

i) Would it make more sense to have the vinegar or the baking soda as the Limiting Reactant. Explain.

ii) Was the volume you calculated more or less than the actual volume of the gas produced? Explain.

iii) How should the pressure you calculated compare to the atmospheric pressure that day? Don’t answer how did it compare but how should it compare. Explain.

iv) With these things in mind, what conclusion would you now make about your data?

Explanation / Answer

i)

The baking soda, since it is solid, and easier to manipulate/add to the liquid baking soda

Therefore, the vinegar will be receiving small amounts of baking soda

ii)

If you made stoichiometric relationship, and used excess vinegar + limiting reactant of soda ash, then there should be LESS gas than the one you claculated

iii)

Note that barometric pressure changes with days, since it depends on weather conditions, so if P is high, then there is more gas, if P is lower, then there is less vapor volume

iv)

Conclude that you should always perform the experiment the same, using exact sotichioemtric ratios and taking in consideration the vapor pressure of water and gas

Related Questions

Navigate

• Browse (All)
• Browse O
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.