The effect of sound on chemical reactions

[Redrang604]

Does sound have a measureable affect on the rate of reaction or equilibrium. If so what would be a good way to go about measuring its effect

[insane_alien]

unless its a highly unstable chemical like nitroglycerin then no it won't have an effect. the only effect it could have anyway is to provide the activation energy and get a reaction started. it won't affect the equilibrium or rate of reacion.

[VendingMenace]

if it provides the activation energy, then it MUST affect the rate of the reaction, by definition.

 

consider this, DNA is a fairly stable molecule and left in liquid it will retain the phosphate backbone linkages for a fiar amount of time (days). However, if you put DNA into a sonicator (a water bath through which high energy sound is pumped), you can break it up into many tiny pieces, effectively speeding up the process of degredation (breaking of the phospate bonds).

 

So, yes, sound can affect the rate of a reaction.

 

I cannot think of anyway that sound would effect the equilibrium of a reaction (at least not of the top of my head) but that is a very interesting question. I will think more about it.

[YT2095]

wahey VM! long time no see dude

 

yes, sound (vibration) will of course affect reaction rate with many processes.

[insane_alien]

didn't know that. oh well.

[Redrang604]

Sound would affect the equilibrium becasue if you add kinetic energy the reaction would equalize towards the endothermic side by la chatelier's principle

 

I was thinking that maybe I could create a setup that allows me to measure the pH of a solution with and without sound input. The question I am really posing is:

1. Is this in any way practical

2. If so how should the speaker be setup next to the solution or somehow in it?

3. How sensitive would the equipment have to be to detect this change. Would a thermometer sensitive to a tenth of a degree C be able to pick up the change?

4. Does anyone have a better setup to determine this?

[Borek]

ARe you planning to measure pH with termometer?

 

AFAIK sound waves from normal loudspeaker will not have energy high enough. You need higher frequencies, that's why in sonochemistry ultrasounds are used.

 

Best,

Borek

--

Chemical calculators at www.chembuddy.com

equation balancer and stoichiometry calculator

www.pH-meter.info

[RyanJ]

Well, [ce]NI3[/ce] can be set off by loud sounds but it is highly unstable. for more reactions the effect of normal sound waves is neglegable at best - its better to simply use heat.

 

Cheers,

 

Ryan Jones

[greg1917]

"Ultrasound can produce temperatures as high as those on the surface of the Sun and pressures as great as those at the bottom of the ocean. In some cases, it can also increase chemical reactivities by nearly a millionfold"

 

http://www.scs.uiuc.edu/suslick/britannica.html