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What is the chemical formula for hydrochloric acid? Write your answer on the whiteboard.
HCl
What gas is produced as a result of the chemical reaction? HINT: The chemical formula is SO2.
Sulfur dioxide
What colour was the precipitated sulphur at the bottom of your test tube?
Yellow
Was the reaction endothermic or exothermic?
Endothermic
Rap a verse about the Sodium Thiosulfate + Hydrochloric acid. (Must mention at least 3 relevant scientific facts i.e. Solid sulfur sediment, endothermic reactions, chemical changes, sulphur dioxide gas formation, colour change etc.)
Nice bars
A student completes the experiment but sees no solid sulphur form at the bottom of the test tube. Suggest two errors they may have made.
Using hydrochloric acid that is too diluted, the room was too cold, they used the wrong/contaminated/expired reagents, etc.
What extensions could you make to the experiment to explore a new variable or phenomenon? Name two.
Different concentrations of hydrochloric acid, the effect of temperature on rate of reaction, test how cloudy the solution becomes (cross test) etc.
What would happen to the rate of your reaction if you used ice cold hydrochloric acid?
The rate of reaction would slow down due to lower particle energy. (No heat to absorb, particles come into contact with each other less often)
What were the two reactants in our experiment?
Hydrochloric acid and Sodium thiosulfate
Spelling bee! You have to spell a word of my choice.
Hydrochloric acid
Draw a rough graph of your group's data on the whiteboard. Must include: scale (doesn't have to be perfect), axis titles and a trend line.
Points if graphed correctly.
POV: Your lab partner added water to the hydrochloric acid without you knowing. How would this affect your experiment?
The rate of reaction would slow down as there is a decreased concentration of HCl.
Explain what happened in the experiment as though you're talking to a first grader.
Mention: reactants, precipitation reaction, gas creation, endothermic reaction
Why is it important to perform this experiment in a well ventilated lab?
The sulphur dioxide gas released is a skin and eye irritant.
A student stored their sodium thiosulfate on a hot windowsill for several days. Once it was time to perform the experiment, they found that the reactants acted strangely. Why might this be?
Heat can cause sodium thiosulfate to decompose or degrade over time, affecting its reactivity.
Debate time! Each team picks a representative. You are arguing the following topic: 'Should we replace this experiment with virtual simulations as a means to avoid inhaling gas irritants?' I will assign sides.
Whoever is most convincing wins.
