Question

1 Chemistry Lab Q:
The reaction that you will be investigating is the reaction that occurs when an Alka-Seltzer tablet is placed into a given amount of water.

Answer 1

i need help with this:

C(graphite) + O2(g) → CO2(g) + 94.05 kcal

C(diamond) + O2(g) → CO2(g) + 94.50 kcal

What could you infer from the information given above?

-The enthalpy of CO2is greater than the reactants.
-E2- E1is negative.
-Graphite and diamond have equal enthalpy.
-Diamond must have lower internal energy.

Answer 2

@marine_poolee_17 Don't drop your own questions in other people's questions. Make a new topic..

Answer 3

While your here, would you like to help?

Answer 4

there. i asked a new topic...

Answer 5

The ingredients of an alka-seltzer tablets are sodium bicarbonate and citric acid.
When placed in water these 2 will react with eachother producing sodium citrate, carbon dioxide (bubbles) and water

In a reaction equation this will be:
\[C _{6}H _{8}O _{7} (aq)+3NaHCO _{3}(aq) \rightarrow Na _{3}C _{6}H _{5}O _{7}(aq)+3CO _{2}(g)+3H _{2}O(l)\]

Answer 6

In this investigation, you will design an experiment to determine what two factors will increase the rate of the reaction above, and then compare the effectiveness of each factor. It is important that in each investigation you control all other variables that could affect the rate of the reaction.

Answer 7

@thomaster

Answer 8

Factors that can increase reaction rate:
-Higher concentration
-Higher pressure
-Higher temperatures
-Stirring

Answer 9

How would you compare the effectivness

Answer 10

@thomaster

Answer 11

the reaction rate will increase if you add 2 or more tablets to the water at the same times, you will get twice the bubbles by adding 2.
I think the pressure and temperature wont increase the rate as much as increasing concentration and stirring will do. If you pound the tablets with a stirrer and it falls apart the rate will increase too as the surface is increased.

Answer 12

If you need to do this experiment in a lab i would suggest increasing concentration and temperature. With these too you can see very good that increasing concentration will increase the rate more then the temperature if you just heat it by 50C or something or add 2 tablets

Answer 13

Your a life saver!
If its not too much trouble, do any procedures of how you would conduct the experiment?

Answer 14

@thomaster

Answer 15

well your variables are concentration and temperature.
I don't know if it's the intention to grind the tablets but if it is you can add different grams of powder to the solution.
If not just add 1 tablet to a beaker with water and to another one 2 and maybe one more with 3 tablets. For both ones observe how intense the reaction gets. if you add 2 tablets there will be alot more bubbles then when you add 1 tablet.
For the temperature part take a heated plate and observe what happens when you add a tablet at different temperatures like the time it takes for the tablet to completely dissolve in the water. It's also important to add the same amount of water to every beaker and test the temperature of the water with a thermometer to determine that te water is at the intended temperature.

You can discuss the results and conclude that the reaction rate increases/decreases.
You cannot conclude which method will increase the rate the most because you do not use the same measured value (time it takes to dissolve whole tablet and most bubbles)
To conclude this you will need to take another factor like stirring and record the time it takes for the tablet to dissolve completely. To do this place a stirbar in the beaker and let it spin at different speeds. In this case your variable is the speed of the stir bar.

Answer 16

You can also check if the rate increases even more if you add tablets to heated water while stirring

Answer 17

@thomaster Thanks so much!! You have really helped.