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Conc sulphuric acid has an affinity for water that is unmatched. The use of this acid will result in lower humidity within the desiccator vessel, which in turn results in faster evaporation from the solution. The speeding effect may not be spectacular (depending on which desiccant we are replacing) but is there. I have actually used conc sulphuric to regenerate desiccants such as silica gel, calcium chloride or calcium sulphate.

Just use a desiccator jar to remove the water. A beaker of conc sulphuric acid can be used as a replacement for normal desiccants. The conc acid will remove water quicker than normal desiccants.

Well if you have a 14C that decays to 14N by beta emission, the 2 elements are fairly compatible. Of course C usually has 4 bonds while N has 3 bonds. N can be in a 4 bonded state as a positive ion. If this decay happens in a protein chain inside your body, possibly a very interesting event has occurred with regard to your health.

Uri the insane one has been telling you the truth. When I specify tolerances for manufacture of small components I often use ±0.01mm. A standard CNC machine will achieve this tolerance quite happily. Still smaller tolerances can be met at a price.

Surely in Hawking radiation the emitted particle has an even chance of being an anti-particle; so emitted particles are primed to change to radiation at their first collision, eventually leaving the universe without matter.

rogerxd45 If you don't know much about respirators then you might be the wrong guy for the job. Your profile does not give your location but here are some details about respirator use in the UK. Indeed there are cartridges available to fit face masks that protect against chlorine. Half face masks are not suitable for use in chlorine contaminated atmospheres unless the chlorine level is truly insignificant. In some circumstances a face mask would not be suitable, and the greater protection of a full suit airline respirator might be needed. An airline respirator requires an air supply, either from a back pack tank or through plastic piping from a compressed air supply. In the UK, before anyone uses a face mask they have to pass a respirator fit test. This certifies that the mask is a suitable fit and is airtight. The size of mask that fits the individual is recorded on the certificate. Unusual facial contours or facial hair can mean a complete fail. In the UK all chemicals need a COSHH (control of substances hazardous to health) assessment before use. In this a suitably qualified and experienced person carries out an assessment of the chemical and the hazards of its use. Steps taken to minimise the risks must be detailed. A COSHH assessment is mandatory. A wider ranging safety case may be needed. Your thoughts that a respirator is required may well be wrong. In devising safe methods of lab work the use of respirators is sort of a last resort. If the chlorine cylinder can be left outside; high integrity piping can deliver the gas to a glovebox or Class 1 fume cupboard. Such a method of working is intrinsically safer than relying on respirators.

You need a solvent extraction. Dry your product thoroughly; then from memory something like propan-2-ol or t-butanol might work. Aldehydes do not like polar solvents. Recrystallise the products from the alcohol.

Well if reports of quark stars are true then colour superconducting quark matter is a real physical state of matter. From the volume and mass of candidate quark stars a density can be ascribed to quarks that matches the way density is calculated for other states of matter. Neutron degenerate matter has a calculated density ~5×1017kg/m3. http://arxiv.org/PS_cache/arxiv/pdf/0709/0709.4635v2.pdf This report uses some concepts that I am not very familiar with, so I will not endorse it unequivocally.

Sphynx The usual way to work out the order of reaction for a reactant is with concentration verses time data for that reactant. The traditional method is to have all the reactants but one in large excess so that a single reactant is followed (a reactant in large excess will have essentially constant concentration). Once the order is worked out for 1 reactant study the next reactant, until the order is known for all reactants. In this case the catalyst will need to be studied as well, probably with a series of experiments in which the amount of catalyst is varied. The order can sometimes be non integer. If you are doing these experiments yourself you should consider the safety implications of working with hydrogen. You would need to write a detailed safety case for working with hydrogen. Extraction to a flame trap is a common requirement for use of molecular hydrogen within a lab. If there is a possibility or likelihood of an explosive atmosphere forming special categories of sparkless equipment would be needed. Finding the order for all ingredients comes before finding the activation energy with Arrhenius. The activation energy you find will only be relevant in the presence of your catalyst. The simplest procedure might be to find a paper written by someone who has studied the reaction. Have you actually looked in your university or company library?

Popular mechanics are not themselves claiming anything. They are reporting claims from a company, who say they are on the verge of putting such a car into production. Apparently such claims have been made for years with no actual cars being produced and no prototypes actually demonstrating the claimed range. Even at 60MPa pressure ~9000psi compressed air contains far far less energy than petrol per litre. Compressed air is just not a good enough energy source for long distance car journeys. Using grid electricity to compress the air is highly inefficient, as all the heat energy imparted to the compressed gas is wasted. As the air expands upon release for use in the engine it cools drastically, some sort of heater or heat exchanger will be needed to keep the system at reasonable temperature. Do not mortgage your house to invest in this technology as thermodynamics says it cannot work.

Sphynx My first point would be that CO2 and 3H2 are not all going to meet at once. This 4 molecule collision is statistically virtually impossible. The reaction will proceed in stages involving 2 molecules at a time. CO2 is actually a fairly stable molecule, it will take a heavy duty reduction system to achieve anything. The system will involve some sort of catalyst; almost certainly a transition metal or rare earth. The catalyst will be involved in the reaction kinetics, it will have an activity coefficient and reaction rates will very likely depend on the surface area of the catalyst. In some circumstances catalysts can be 'poisoned' as the reaction proceeds losing effectiveness. Next point is whether the reaction really finishes at methanol. Is there a reason inherent in the conditions why the methanol cannot be reduced by a 4th H2 to produce methane and water? From the data provided this cannot be ruled out.

You should read about the water equilibrium constant Kw. Hydronium and hydroxide ions are always in equilibrium with molecular water.

Pressure vessels have special regulatory requirements. In the UK the safety relief systems need to be reset every 12-14 months. The pressure vessel itself requires an internal and external examination by an expert; alternatively a hydraulic pressure test to 1.5 times the rated pressure is carried out. This is not a convenient procedure to carry out on a vehicle. The weight penalty from containment for gas at 4000psi is high but somewhat offset by weight savings on a simpler engine. The real problem is that compressed air is outperformed as an energy source by just about any other option usable in a vehicle. Compressed air cars are not coming to a showroom near you because they do not make engineering sense.

Remember that to use Arrhenius correctly you should only consider the chemical species involved in the Rate Determining Step. A little knowledge of the kinetics of your reaction is needed before you use Arrhenius.

Try the Fisher Scientific catalogue. http://www.fisher.co.uk/catalogues/laboratory_catalogue.php

insane_alien I don't want a bitter disagreement with you as actually I agree with you on the vast majority of your thoughts. The link I provided states explicitly that 'The fission energy contained in the reserves is far greater than all fossil fuels on the earth combined (even including methane clathrates), without even considering the use of fast breeder reactors utilizing byproducts like plutonium.' That is far more than 4 or 11 years of worldwide use for nuclear power. The authors may have miscalculated, or they may have included reprocessing to MOX fuel and the use of non breeder fast reactors; both of which gain much more energy from the original UO2. Your Scientific American link may just consider an American perspective. Some American sources seem to consider that American practices are the best and only way. No USA reactor has ever used MOX fuel, whereas many European reactors have done so. Fast reactor studies stopped many years ago in the USA, but continue in France, Japan and Russia. Stating that 99% of Uranium is non fissile is both true and slightly misleading. Natural uranium at 0.71% 235U can be made to go critical quite happily. The predominant 238U will produce some interesting fissile isotopes for MOX or use in a fast reactor. Enriched U is used in reactors to obtain criticality with less moderation, and it also enables easier extraction of power from the coolant in a denser core.

insane_alien Your post 19 was was very well reasoned, however I would have to take issue with the following passage. You are grossly underestimating the uranium reserves. Known uranium reserves contain more energy than all known fossil fuel reserves. http://wapedia.mobi/en/Uranium_reserves. This is without considering that prospecting has not taken place in many of the geological areas likely to contain uranium ore. Major finds of uranium ore are likely. On the other hand extraction of lower grade ores will require more energy to be used in the extraction and produce more nasty mining waste. Use of MOX fuel will improve the bang for the buck in the next generation of nuclear reactors, but as you said FBRs will be needed to keep the world's lights on for more than the next few decades. There is a huge stockpile of 238U waiting to be turned into burnable fuel. Waste disposal may be a problem as proper storage facilities are lacking, due to lack of political will. One viable waste disposal method may be subduction into the mantle; the Marianas Trench may be one suitable location. Adoption of full nuclear fuel cycle could keep the world's base load supplied for centuries while we sort out fusion or space based solar power or build a Ringworld.