[Entrigued]

Could the reaction between nahco3 and dilute hcl be used to make a chemical car? Given that acetic acid is normally used, could hcl acid replace it. I think it causes more propulsion given that it is a much stronger oxidizing agent. Please answer from experience with these two compounds.

[cth]

I think it causes more propulsion given that it is a much stronger oxidizing agent.

HCl is acid, but it isn't an oxidant.
HCl is a stronger acid than acetic acid, so its reaction with NaHCO₃ will proceed faster:

HCl + NaHCO₃  NaCl + H₂O + CO₂
releasing CO₂ as a gas.

It depends on the concentrations used, but expect this reaction to be violent and fast.
Possible projection of acidic droplets out from the beaker when CO₂ gas bubbles break at the solution surface.
Possible formation of an abundant foam.
So, take adequate safety precaution: lab coat + safety glasses + gloves in a well ventilated place when handling HCl.

Do you intend to use CO₂ as a car propellant?

[renge ishyo]

Do you intend to use CO2 as a car propellant?

What they do is they trap the CO₂ in the bottle and then release the lid to propel the car all in one burst. See here for an example setup: http://engr.oregonstate.edu/momentum/k12/march04/index.html

[cth]

OK, I see the kind of car it is: a Porsche for guinea pigs.   


One shouldn't close tight the bottle containing HCl and NaHCO₃, or else it may explode due to the overpressure of CO₂.

[renge ishyo]

One shouldn't close tight the bottle containing HCl and NaHCO3, or else it may explode due to the overpressure of CO2.

I think that is more or less the reason why they use acetic acid instead of HCl. I mean unless they are trying to imitate a real Porsche by having it break down before you use it.

[Entrigued]

I think it causes more propulsion given that it is a much stronger oxidizing agent.

HCl is acid, but it isn't an oxidant.
HCl is a stronger acid than acetic acid, so its reaction with NaHCO₃ will proceed faster:

HCl + NaHCO₃  NaCl + H₂O + CO₂
releasing CO₂ as a gas.

It depends on the concentrations used, but expect this reaction to be violent and fast.
Possible projection of acidic droplets out from the beaker when CO₂ gas bubbles break at the solution surface.
Possible formation of an abundant foam.
So, take adequate safety precaution: lab coat + safety glasses + gloves in a well ventilated place when handling HCl.

Do you intend to use CO₂ as a car propellant?

It is a fact that all acids are oxidants. Therefore, your first claim is void, which reduced your credibility. The other inferences are accurate, but here are the conditions. I'm planning on using things found around the household. For hcl it is some cleaner detergent since most bleaches contain hcl, I'm pretty sorry it is in safe concentrations. Yes, I do intend to use co2 as the propellant.  It's  actually the pressure built up in the bottle that will propel it. the nahco3 is from baking soda. Please, do a little research before your response. thanks for responding.

[Entrigued]

OK, I see the kind of car it is: a Porsche for guinea pigs.   


One shouldn't close tight the bottle containing HCl and NaHCO₃, or else it may explode due to the overpressure of CO₂.

Thanks a lot.

[Borek]

It is a fact that all acids are oxidants.

H⁺ is an oxidizer, so technically yes, all acids are oxidizers. However, when we speak about oxidizing acids we usually mean those that are stronger oxidizers - like nitric acid.

[cth]

It is a fact that all acids are oxidants. Therefore, your first claim is void, which reduced your credibility.

No need to be unpleasant. 
In absolute, you have:  2H₃O⁺ + 2e^-  2H₂O + H₂
so yes, all acids can potentially be oxidant if they are in the presence of a strong enough reducing agent.
But, you wrote:

Could the reaction between nahco3 and dilute hcl be used to make a chemical car? Given that acetic acid is normally used, could hcl acid replace it. I think it causes more propulsion given that it is a much stronger oxidizing agent. Please answer from experience with these two compounds.

In your case, it is an acid-base reaction, not an oxidation reaction. So, when I said "HCl is acid, but it isn't an oxidant", I should have added "in your case". Nevertheless, this point still needs to be clarified. Anyone with a minimum of chemical background shouldn't mix up oxido-reduction with acid-base reactions.

I'm planning on using things found around the household. For hcl it is some cleaner detergent since most bleaches contain hcl, I'm pretty sorry it is in safe concentrations.

The active molecule in bleach is NaOCl, sodium hypochlorite. Thanksfully it doesn't contain HCl, because in acidic solution, bleach decomposes to form Cl₂ gas, which is very toxic:
H₃O⁺ + Cl^- + HClO  Cl₂ + 2H₂O
So first, you will find NaCl in bleach, but not HCl.
Second, don't ever think about adding HCl into bleach.
Third, bleach and NaHCO₃ won't work to produce CO₂.

Please, do a little research before your response.

I do research every day, it is my job as a postdoc. And I suggest you refresh your basic knowledge about chemistry.

Finally, HCl is written with capital letters, not as "hcl". The same for NaHCO₃,... It is important to avoid any confusion. For example, if I write "cli", how would you know if it is CLi (carbon and lithium) or ClI (chlorine and iodine)?

[Borek]

cli means CLear Interrupts, programs like

cli
halt

or

label:
cli
jmp label

were a simplest way of hanging early computers

[renge ishyo]

It is a fact that all acids are oxidants. Therefore, your first claim is void, which reduced your credibility. The other inferences are accurate, but here are the conditions. I'm planning on using things found around the household. For hcl it is some cleaner detergent since most bleaches contain hcl, I'm pretty sorry it is in safe concentrations. Yes, I do intend to use co2 as the propellant.  It's  actually the pressure built up in the bottle that will propel it. the nahco3 is from baking soda. Please, do a little research before your response. thanks for responding.

And the award for the most needlessly insulting post of the week goes to...*drumroll*...Entrigued

In all seriousness guy, it is a bad idea to substitute HCl for acetic acid because the *rate of the production of CO₂* (which is the only thing that would be faster by using HCl instead of acetic acid) has no bearing on how fast your car will ultimately go. Rather it is the *amount* of CO₂ produced in the bottle that leads to the pressure buildup that is ultimately released all at once that gives your motion. Therefore, what you want to make the car faster is as much bicarbonate transformed into CO₂ inside the bottle as possible. To do this you need to add an EXCESS of acid (not a dilute solution) to get all the bicarbonate to react and shift the equilibrium towards CO₂. It goes without saying (even though I am going to say it) that adding an excess of concentrated HCl to your bottle would not work well...that idea would, quite literally, blow up in your face.

Instead of using a strong acid, they add a *large amount of a relatively weak acid* so that the rate of production is slow enough to build up the CO₂ level inside the bottle without leading to an explosion. Since the car is ultimately propelled by the amount of CO2 that is suddenly released this will get you a good result even though the acid is weak (its designed that way on purpose!). If you want to improve the speed of your car, I suggest considering other things such as the nature of the tires, the overall weight of the apparatus, the aerodynamics of the bottle you are using, etc.

[Entrigued]

It is a fact that all acids are oxidants. Therefore, your first claim is void, which reduced your credibility.

No need to be unpleasant. 
In absolute, you have:  2H₃O⁺ + 2e^-  2H₂O + H₂
so yes, all acids can potentially be oxidant if they are in the presence of a strong enough reducing agent.
But, you wrote:

Could the reaction between nahco3 and dilute hcl be used to make a chemical car? Given that acetic acid is normally used, could hcl acid replace it. I think it causes more propulsion given that it is a much stronger oxidizing agent. Please answer from experience with these two compounds.

In your case, it is an acid-base reaction, not an oxidation reaction. So, when I said "HCl is acid, but it isn't an oxidant", I should have added "in your case". Nevertheless, this point still needs to be clarified. Anyone with a minimum of chemical background shouldn't mix up oxido-reduction with acid-base reactions.


  I am sorry if I came across rude. Your right this is an acid and base reaction, however reduction, occurs when the oxidation number of a particular element of a reactant is reduced, a reduced element is referred to as a oxidant, and oxidation still occurs during these reactions. There are clear distinction between Redox and acid-base reactions, and I am clear on all of those premises. I am thankful for your input, it is much appreciated, no insult intended.

I'm planning on using things found around the household. For hcl it is some cleaner detergent since most bleaches contain hcl, I'm pretty sorry it is in safe concentrations.

The active molecule in bleach is NaOCl, sodium hypochlorite. Thanksfully it doesn't contain HCl, because in acidic solution, bleach decomposes to form Cl₂ gas, which is very toxic:
H₃O⁺ + Cl^- + HClO  Cl₂ + 2H₂O
So first, you will find NaCl in bleach, but not HCl.
Second, don't ever think about adding HCl into bleach.
Third, bleach and NaHCO₃ won't work to produce CO₂.

Please, do a little research before your response.

I do research every day, it is my job as a postdoc. And I suggest you refresh your basic knowledge about chemistry.

Finally, HCl is written with capital letters, not as "hcl". The same for NaHCO₃,... It is important to avoid any confusion. For example, if I write "cli", how would you know if it is CLi (carbon and lithium) or ClI (chlorine and iodine)?

I am aware of that and will ensure that I adhere to that rule since it may cause ambiguity.  No indeed, to be defensive  , I sincerely apologize for questioning your credibility. Keep up the good work.