[mheever]

Why must EFFERVESCENT TABLETS be dissolved in tap water? 

[Arkcon]

It really depends on the application at hand.  Can you tell us some more about what you're doing/what this is for?

[mheever]

hehe cerntainly . it's a science question for my school report in which i must explain why the manufacturers insist that EFFERVESCENT TABLETS must be dissolved in tap water. I couldn't get any good reasonable answer to the question .
Thx alot 4 the help.

[Arkcon]

Well, what other liquids are there available to you, and can you tabulate what might happen?

[mheever]

Well, I thought it  that the temperature of the water is relevant: the fizzy tablet is a solid and needs kinetic energy to be dissolved - so, cold water won't work. On the other hand is the carbon monoxide production important to disperse the active ingredients in the fizzy tablet - however if the temperature is too high, the solubility of the CO2 decreases and as a result also the benefit of the CO2-production to disperse the active ingredients. Therefore room temp of tap water would be the answer to benefit both reactions. Also, if the temperature is too high the active ingredients may be of less or no value. What do you think?

[Arkcon]

That's a good first step.  'Tho I'd watch the spelling -- carbon monoxide is not what you want in an effervescent tablet. 

[lutesium]

Well, I thought it  that the temperature of the water is relevant: the fizzy tablet is a solid and needs kinetic energy to be dissolved - so, cold water won't work. On the other hand is the carbon monoxide production important to disperse the active ingredients in the fizzy tablet - however if the temperature is too high, the solubility of the CO2 decreases and as a result also the benefit of the CO2-production to disperse the active ingredients. Therefore room temp of tap water would be the answer to benefit both reactions. Also, if the temperature is too high the active ingredients may be of less or no value. What do you think?

What do you mean by tap water??? His temperature or his mineral content or his density??? Maybe your teacher might have thought of the active ingredients of the tablets which might change their molecular structures above certain temperatures and so if they're dissolved in hot water or there's nothing to be afraid of if they're dissolved hotter water as mentioned above!!! There's no need to disperse the active ingredients... And yes dissolvation is endothermic so he needs external energy but the dissolvation being too slow cold water does also work. And the chemical reaction involved is NaHCO3 + Citric Acid ===> Sodium Citrate + H2O + CO2 => Carbon Dioxide not Monoxide. Carbon Monoxide is CO!!!


Lutesium...

[mheever]

Sorry for the monoxide - I was in a rush to answer quick and made a spelling mistake. I used the term tap water because it is the way the question was put to me - the teacher didn't gave any info except for what I sent to the forum. Thanks any way for the inputs.

[typhoon2028]

Why must EFFERVESCENT TABLETS be dissolved in tap water? 

I believe this may be a disclaimer for idiots who would try swallow an Alka-Seltzer tablet. 

[Arkcon]

Why must EFFERVESCENT TABLETS be dissolved in tap water? 

I believe this may be a disclaimer for idiots who would try swallow an Alka-Seltzer tablet. 

When I did dissolutions for finished tablets at a pharma company, I always did them in the approved media, which was often degassed, deionized, water.  I often asked people, anyone ever research spiking the dissolution chamber with ethanol, to mimic someone washing down their heart medication with half of a fifth of Scotch?