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No it does not mean exactly that. Liquid in deodorant bottle is at great pressure. If it gets out it starts to evaporate. Any part that evaporates takes a lot of heat with it, so liquid that remains ( for example on your body ) goes colder and colder as long as it is not yet completely evaporated. Fridges use this to make cold but there all the process goes in the copper tubes. In the same reason acetone or gasoline go rather cold if vessel is left open and even water that stands in open beaker at your desk is always some degrees colder than air around it. In respect of this "colder" liquids are those that evaporate fastest but only if they can freely evaporate.

Just read from one russian book why graphite electrodes are pulverized! Oxygen indeed is guilty of this. It partly reacts with carbon making some CO2. Electrode surface changes to something porous and small particles start to fall apart. Concentration of NaCl in those pores is lower than in other areas of electrolyte and so there tends to go just electrolysis of water that gives even more oxygen. According to this book even high quality graphite is always rather porous. There is also description of process for treating graphite electrodes in vacuum and soaking into linesed oil to get rid of pores. They also tell that amount of oxigen depends on current density and is lowest somewhere near 0.1 A/cm2. There are two real life industrial electrolysers described here - one with current density 0.07 A/cm2 another 0.02 A/cm2 both use graphite anodes. edit: higher current densities are used when making peroxyacids or peroxides. Those use currents of 0.5 ... 0.7 A/cm2 and as a rule platinum anodes. Still higher current densities make even paltinum electrodes unreliable because electrode destruction.

I think destruction of electrodes is mostly due of low quality of carbon we use. Graphite from pencils will be pulverized very soon, that from batteryes is better but not much. Destruction of electrodes depends also of current densitiy. Thats amount of electrical current flowing through electrolyser divided by surface area of electrode. Professional electrolysers never use more than 0.5 A/cm2 but more often 0.07 ... 0.1 A/cm2. If we use graphite rod with diameter of 7mm thats soaked 5cm into electrolyte then working area is 0.7 * 3.14 * 5 = 11 cm2, aproximately 10 cm2 so 1A of current will give current density 0.1 A/cm2. If you use graphite from pencils then acceptable current may be 100mA or even less. Current source is a must especially if you want deposit metals from solutions. If you have controll over current you can get more use of Faradays law too. And you will have better repeatable results. I made mine using only one IC: LM317 3-pin adjustable voltage regulator that can also be connected as current source. You have to replace reistor R1 with potentiometer (something like 22 ohms is good). Output current of circuit is 1.2 / R1 . Output voltage may change from fractions of volt to almost input voltage ensuring with this that output current stays at the value set by potentiometer even if resistance of load changes. For foolproofing the device i connected 1 ohm reistor to the output line so output resistance will never be lower than 1 ohm even in if electrodes in electrlyser are short-circuited (this resistor can also be used as current sensor). LM317 must be in heatsink and better yet with small fan from old computer processor. Max output current is 1.5A, max input voltage is something over 30V. 24V adapter is good for input. Not-very-high output current is drawback of this circuit. Something like 10A would be much better but this is not very realistic with reistive regulators even when using transistors to increase output power. Swithmode is needed for this but thats not thing i am currently able to design. LM317 data sheet: http://www.national.com/pf/LM/LM317.html

I too know these problems with anode. I think this is mostly due of low quality of carbon electrodes we use. Graphite from pencils will be pulverized very soon, that from batteryes is better but not much. Destruction of electrodes depends also of current densitiy. Thats amount of electrical current flowing through electrolyser divided by surface area of electode. Professional electrolysers never use more than 0.5 A/cm2 but more often 0.07 ... 0.1 A/cm2. If we use graphite rod with diameter of 7mm thats soaked 5cm into electrolyte then working area is aproximately 10 cm2 so 1A of current will give current density 0.1 A/cm2. If you use graphite from pencils then acceptable current may be 100mA or even less.

Acetic acid will not decompose but evaporation rates of water and acid are almost equal. You have to evaporate 90% or even more of liquid to get residue that is remarkably more concentrated than your initial product.

HCl is colorless, brown gas can be seen if you make nitric acid and even then most of gas is colorless. Suckback is a problem when dissolving gas in water. I usually leave gas tube slightly above the liquid - all gas will dissolve almost as well. Of course you need fume hood for this. As rogh estimate you need equal weights of sulfuric acid and salt. It seems that you have not enough experience with labwork to do this succesfully. Its good idea to spend some days disitilling just water or boiling out table salt from solution. This may seem useles but in fact will give you a lot of invaluable experience.

You may try with vinegar or acetic acid. Sometimes it works. I usally do this with boiling battery acid.

Is not NaCl for salting out soap? After fats are saponified product is dissolved in mixture of water and glycerin. If NaCl is added soap separates as upper layer, most of glycerin and water remaining in pot.

My most dangerous chemicals are red fuming nitric acid, concentrated sulfuric acid (at 270C), bromine, chlorine and H2S - nothing very special but all selfmade (expect sulfuric acid that was self-concentrated).

Aqueous solutions of alkali cyanides can dissolve gold and are used for gold plating. Its also important intermediate in organic synthesis, for example to make nitriles. There are more uses but these are first to remember. Alkali metal cyandies are used instead of HCN whenever possible because HCN due of its volatility is much more dangerous.

I got it from bee-keeping shop. It was sold as disinfectant.

I made formic acid esters today! To make ethyl formate: mixture of formic acid 85%, ethanol 80% and battery acid (H2SO4, 35%), 1...2ml of each, was heated in test tube during 5 min near the boiling point. Strong smell was noted, different from other esters i have synthesised so far. I also made methyl formate for comparision using 80% methanol instead of ethanol. Smell of methyl formate is almost the same but not so strong.

For organic chemistry: http://www.cem.msu.edu/~reusch/VirtualText/functbl.htm For MSDS datasheets and safety information: http://physchem.ox.ac.uk/MSDS/

Butanol can be made by fermentation. If i rem it right just like ethanol but with different bacteria. I plan to experiment with this someday if i have more time.

Isoamyl alcohol is one of pentanol isomers. Its usally made by separating from fusel oil. Fusel oil is byproduct of ethanol (or moonshine) manufacture. Does anyone know more handy way to get it?

Another very easy ester. I droped into test tube one tablet of nonfizzing aspirin, some milliliters of 80% ethanol and some milliliters of battery acid. After heating during twenty minutes on hot water bath mixture developed strong smell. It smells even now rather good and not like ethyl acetate. After standing some hours on cool place there appeared nice needlelike crystal on bottom of test tube. I do not know what it was. Maybe unreacted aspirin. And ester... I do not know. Probably ethyl salicylate.

Geting high conc acetic acid is even harder than woelen said here. I have tried this and no, boiling it to half volume does not double its conc. To get 70% acetic acid from 30% i had to boil it to less than one fifth of initial volume. Freezing also does not work because freezing point of 30% acetic acid for example is so low that -18C does nothing to it. 80% acetic acid can be frozen but even then liquid phase is mostly absorbed by solid so you do not get acceptable separation. Useable way is to distill waterfree sodium acetate with conc. sulfuric acid. Sulfuric acid has to be near 100% because almost all the water it has distills over into your acetic acid. So its one of those chemicals you have to buy somewhere.

Most easy ester to synthesise is probably ethyl acetate. If smell is all that is desired one can use almost any acetic acid (including 6%), some drops of sulfuric acid (battery acid is ok) and some vodka instead of ethanol. If mixture is heated there will soon be smell of ethyl acetate. Be cautious though - never bend over hot liquid. Sudden boiling may occur and you may get all this onto your face.

Very old way of making sulphuric acid is by heating FeSO4 * 7H2O to decomposition and collecting vapors. Salt loses crystallisation water at first and after that gives of sulfur oxides including SO3. This is rather expensive way and product will be contaminated but it may still be useable for small experiments. Have not tried it myself though.

Why reaction Ca(OH)2 + (NH4)2SO4 goes to direction of producing ammonia? Part of gaseous ammonia will left reaction area as soon as it is produced and so reaction in bacward direction can not go very effectively. There is no equilibrum before all ammonia is left. This principle applies to any reaction where one of products is in gaseous state.

Electrolysis is rather complex process with many side reactions so there is no single answer. You will surely decompose (or evaporate) all the water. What remains is complex mixture of substances. If you started with NaCl then you will be left with some NaCl, NaOH, NaClO, NaClO3, NaClO4. If electrodes are not completely inert you will also get oxides/hydroxides of electrode material and probably chlorides/chlorates as well. Exact proportions of your products depend on electrode material, temperature, current density and many other things.

All depends of structure. If it is just mixture of substances then cold may help to separate them. Water is not just mixture - new particles are formed and those need lot of energy to decompose. You can still decompose water into H2 and O2 by strong heating (because heating can supply that energy) but not by freezing.

Cr2O3 can be made soluble (converted to sodium chromate) by fusing it with NaOH especially if some oxidiser (like KNO3 or NaNO3) is added. Maybe this works with other oxides too?