Home Chemistry 11 – Making a Citric Acid solution

Further to the previous post on making molar solutions I am going to make up a 250ml solution of Citric acid.

So based on my previous calculations

1 Molar solution is formula weight in 1 litre of Water

Molar Weight of Citric acid 192.19 Amount of Water = 250ml (0.250 l)

Therefore

192.19 / 4 = 48.03g

I can weigh this out easy enough now that I have got some small scales (which are actually used for weighing jewellery) but are really good as they measure to 2 decimal places. Granted max is about 200g, but for what I am doing in chemistry this doesn't matter too much.

The first task is to weigh out the required amount of Powder.

Given I wanted 48.03g, I think for the purpose of home chemistry this is fine.

For the next step I mixed the powder with about 200ml water, stirred well then poured (via funnel) in to a conical flask and topped up to about 250ml (note the flask is approximate.) I may be just over. in a proper laboratory, I would have access to a volumetric flask, which is more accurate. I am making do with what I have.

I would probably have access to some help with this too.

Finally, the solution is poured (via funnel) in to a suitable bottle, that I have already put a label etc on.

This is now stored safely before being taken down to the Library.

We can then use this for various experiments such as adding to alkalis, using indicator (paper or liquid) or whatever else we decide to do).

There is a really nice calculation tool which you can use to help or at least double check calculations.

#HomeChemistry11,#Chemistry,#Science,#HomeChemistry,#CitricAcid,#Solution,#Molar,#Concentration

Home Chemistry 7 – Reactions of metals with White Vinegar

Further to my previous experiment. Yesterday I added Magnesium Ribbon to some White Vinegar.

The video doesn't seem as good, part the issue is the light the other issue is the bubbles of Hydrogen produced do get in the way a little.

Video

Link

• Science Forums

Tags

#Chemistry,#HomeChemistry,#Magnesium,#WhiteVinegar

Home Chemistry 6 – Reactions of metals with Citric Acid

So while I wait for delivery of some more indicator paper. I am going to take a look at how Magnesium reacts with Citric Acid.

Firstly as indicated in a Previous post it is important to ensure the Magnesium metal is clean and free of tarnish. This will aid the reaction by exposing a greater surface area of the metal.

I will be using the same equipment as before,

As well as Citric Acid, which is shown here along side Bicarbonate of soda.

I decided to use a conical flash instead of a test tube and this makde it a little easier to observe the reaction.

I added some Citric Acid powder to the flask, added about 50ml water to dissolve the acid then added one piece of Magnesium ribbon, approx 1” long to the solution.

Took a few mins to get going, once the remaining tarnish had gone, the reaction speeded up.

Video

Link

• Science Forums

Tags

#Chemistry,#HomeChemistry,#Magnesium,#CitricAcid

Home Chemistry 5 – Electrochemical Series

As it was suggested revise the Electrochemical on Science Forums. I am including a video from youtube on this topic.

This is presented by Fuzeschool Global Education

Happy to discuss on the Fediverse, but it would be better to ask on Science Forums.

Tags

#Chemistry,#Reactivity,#ElectroChemicalSeries,#HomeChemistry

Home Chemistry 4 – Indicators

For some reason, the universal indicator paper I have isn't working properly, it could be as it is quite old.

Nevertheless it does seem that if emersed in Water, the chemicals within leech out. I tried this with a few pieces and it has produced a nice blue colour.

So I am assuming that the liquid produced can act as an acid / alkali indicator.

So to investigate further. I am going conduct an investigation.

Equipment

• Test tube rack
• 2 Test tubes
• Beaker with indicator solution
• Dropper
• Spatula

Chemicals

Both in powder form.

• Bicarbonate of Soda
• Citric Acid

Predictions

• Bicarbonate of Soda – Should change colour towards Purple (Alkali)
• Citric Acid – Should change colour towards red (Acid)

Method

• Add Bicarbonate of soda to 1 test tube
• Add citric Acid to the other
  • Make a note which is which
• Using a dropper add some of the indicator to each of the test tubes
• Note colour

Results

Colour changes noted as follows:-

• Bicarbonate of Soda – Stays blue
• Citric Acid – Does turn a very pale pink colour

Conclusions

1. I don't think I had an indicator in the first place, as this was blue,any change in colour would not be very noticeable with the addition of the alkaline bicarbonate of soda.

2. I would have expected the citric acid to be a clearer colour to indicate acid.

3. I think my indicator paper is simply out of date due to age.

Recommendations

1. Repeat part of this experiment using fresh indicator paper, only just use the paper to test the above two chemicals mixed with water. As the paper needs a liquid to work anyway.
   
2. Throw old papers away and buy new.

Update

As confirmed on Science forums the indicator paper has degraded and needs to be replaced. So my Hypothesis as to the issue was on the right track.

Links

• Discussion on Science Forums

Tags

#Chemistry,#HomeChemistry

Home Chemistry 1 – Follow up

So just posting a follow up to the experiment with a photo of the test tubes.

So we can see From this that the tube on the far left still has Zinc, the one on the Far right has Copper. The centre tube did have the Magnesium, but this is now Magnesium Acetate.

So an interesting experiment.

Testing for Acetate

For those taking a more scientific approach and who may want to test to confirm what is produced the following from Robolab may be useful.

Further reading

I have started a thread on Scienceforums to ask how to decontaminate the other metals. They may need this but it would be good practice not to simply remove from test tubes, leave to dry and put back in the original containers.

Feel free to discuss further on Mastodon. My profile is at https://qoto.org/@zleap

Tags

#Science,#HomeChemistry,#Chemistry,