Bath bomb changing acid
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Jeneric007
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Bath bomb changing acid
I would like to do the bath bomb experiment except change it. Most recipe ratios are 2:1. Why less acid to baking soda or not equal parts ? Doesnt more acid mean more fizz or is there a set ratio for the reaction to happen? I cannot seem to find any information about the effects changing acid amounts and the answer to why I would get more or less fizz ? Do you know the answer ?
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SciB
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Re: Bath bomb changing acid
Hi,
That's a good chemistry question! https://www.sciencebuddies.org/science- ... mb-science
The first thing you need to ask is where does the 'fizz' [i.e., CO2, carbon dioxide gas) come from? The CO2 comes from a chemical called sodium bicarbonate, Na2HCO3 (aka, baking soda). You can see from the formula that it contains 'CO2' as part of its chemical make-up along with hydrogen, H, and sodium, Na [from the Latin, 'natrium'].
But how does the HCO3 of bicarbonate become CO2 gas?
That's where the chemical reaction comes in. Another ingredient in the bath bomb is citric acid, the same chemical that makes grapefruits and lemons taste sour. You can mix citric acid powder and sodium bicarb powder and nothing will happen as long as you keep it dry. However, as soon as the two chemicals dissolve in water [like your bath water] they are able to chemically interact and one of the results is that HCO3 is converted to CO2 gas--the fizz.
When you use baking powder to make biscuits, the rising of the batter is caused by CO2 because baking powder contains baking soda, Na2HCO3, and an acid, just like the bath bomb. When the liquid is added to the flour containing baking powder, the gas begins to be released and as soon as you put the biscuits on the pan and pop them in the oven, the CO2 makes them rise.
I know this is a rather long answer to a simple question, but I thought I would throw in a free chemistry lesson first.
OK. So, your question was would adding more citric acid cause more fizz. The short answer is NO, but it would depend as you imply on the ratio of citric acid to sodium bicarbonate. When the amount of citric acid is exactly sufficient to react with a specific amount of baking soda, then adding more acid will not produce more CO2. In order to get more gas, you would have to add the chemical that the gas came from--Na2HCO3. But then there might not be enough acid, so in that case adding more would increase the fizz. What I am trying to get at is a basic law of chemistry and that is in a reaction, the reactants combine in specific ratios and amounts. These amounts are determined by weight, not by volume as you measured in this experiment as tablespoons. One Tb of citric acid does not weigh the same as one Tb of baking soda.
All this is easy to test by experiment. Just mix different proportions of acid and bicarb and see what happens.
The wild card here is the corns starch. Try the experiment without any cornstarch. What happens? Why is corn starch one of the ingredients of a bath bomb?
OK. That's enough yakking. I hope this has helped. Any more questions? Please ask--that's what we are here for!
Sybee
That's a good chemistry question! https://www.sciencebuddies.org/science- ... mb-science
The first thing you need to ask is where does the 'fizz' [i.e., CO2, carbon dioxide gas) come from? The CO2 comes from a chemical called sodium bicarbonate, Na2HCO3 (aka, baking soda). You can see from the formula that it contains 'CO2' as part of its chemical make-up along with hydrogen, H, and sodium, Na [from the Latin, 'natrium'].
But how does the HCO3 of bicarbonate become CO2 gas?
That's where the chemical reaction comes in. Another ingredient in the bath bomb is citric acid, the same chemical that makes grapefruits and lemons taste sour. You can mix citric acid powder and sodium bicarb powder and nothing will happen as long as you keep it dry. However, as soon as the two chemicals dissolve in water [like your bath water] they are able to chemically interact and one of the results is that HCO3 is converted to CO2 gas--the fizz.
When you use baking powder to make biscuits, the rising of the batter is caused by CO2 because baking powder contains baking soda, Na2HCO3, and an acid, just like the bath bomb. When the liquid is added to the flour containing baking powder, the gas begins to be released and as soon as you put the biscuits on the pan and pop them in the oven, the CO2 makes them rise.
I know this is a rather long answer to a simple question, but I thought I would throw in a free chemistry lesson first.
OK. So, your question was would adding more citric acid cause more fizz. The short answer is NO, but it would depend as you imply on the ratio of citric acid to sodium bicarbonate. When the amount of citric acid is exactly sufficient to react with a specific amount of baking soda, then adding more acid will not produce more CO2. In order to get more gas, you would have to add the chemical that the gas came from--Na2HCO3. But then there might not be enough acid, so in that case adding more would increase the fizz. What I am trying to get at is a basic law of chemistry and that is in a reaction, the reactants combine in specific ratios and amounts. These amounts are determined by weight, not by volume as you measured in this experiment as tablespoons. One Tb of citric acid does not weigh the same as one Tb of baking soda.
All this is easy to test by experiment. Just mix different proportions of acid and bicarb and see what happens.
The wild card here is the corns starch. Try the experiment without any cornstarch. What happens? Why is corn starch one of the ingredients of a bath bomb?
OK. That's enough yakking. I hope this has helped. Any more questions? Please ask--that's what we are here for!
Sybee