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Dilution of concentrated acid should always be done in a fume cupboard.
It is important only to pour acid into water, not the other way around, especially with concentrated acids. Acids may quickly absorb water, creating a lot of heat in the process. When acid is poured into water, the heat can quickly become evenly distributed in the water. If water is poured into acid, the water may quickly boil, spraying acid everywhere.
To make a 1 molar solution (1M):
Add 83.5mL of 36% hydrochloric acid to about 600mL of distilled water in a 1 litre measuring cylinder in a fume cupboard. Make up to 1L, mix well and pour into a labelled bottle.
As above, except use 96mL of hydrochloric acid.
Concentrated hydrochloric acid is highly corrosive and very irritating to the lungs, wear a face shield and use a fume cupboard.
Assuming the concentrated nitric acid is 70 %w/v, then to make a 1M solution:
Add 62mL of concentrated nitric acid to about 700mL of water then dilute to 1L.
Add slowly, stirring constantly with a polypropylene or glass stirring rod. If the solution gets too hot, stop and let it cool down.
Concentrated sulfuric acid is highly CORROSIVE and a dehydrating agent. It causes severe burns. It should only be handled under close supervision by an experienced person. Wear gloves and protect the eyes with safety goggles or even better, a face shield.
Add 54mL of concentrated sulfuric acid to about 700mL of iced water and dilute to 1 litre. This is a 1M solution.
Known also as acetic acid. The concentrated acid is called Glacial acetic acid as it freezes at 17°C. Glacial acetic acid is CORROSIVE and the vapour is an extreme IRRITANT. Wear gloves and protect the eyes with safety goggles or even better a face shield. Work in a fume cupboard.
To make a 1M (mole/litre) solution, add 57mL of the concentrate to about 600mL of distilled water and dilute to 1 litre.
Some substances do not dissolve very readily in water and require special methods.
This dissolves very slowly in water. The best thing to do is to start making it up the day before you need it. Mix the powder into agitated water, then put into the fridge overnight. When you come back in the morning it will have dissolved.
In general, starch is insoluble in water, but some types of starch e.g. corn starch will dissolve in water provided they are made into a paste first with cold water then dissolved in boiling water.
Most iron (III) salts do not form stable aqueous solutions. In order to get them to dissolve you need to add a small amount of acid. Add hydrochloric acid to the chloride etc...