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Hey, I was looking at the reaction between ammonia (NH₃) and hydrochloric acid (HCl). Apparently from the diagram I saw the hydrogen from HCl would get drawn towards the nitrogen, leaving an electron behind for the chlorine. Why does this happen? Do lone pair electrons have a larger electrostatic force? P.S forgive me if I've i may of done something wrong, I'm new to this website.

It won't happen before November, and in this case in collaboration with the NIH, the pre-clinicals will run in parallel to phase I. Roughly speaking, the next steps tend to be more expensive (money and time wise) before a full roll-out can happen. Always assuming that these vaccines actually work. Also note that they are testing three different concentrations to ascertain safety and there is not guarantee that an of them will elicit an immune response (though they will also look at that as a secondary goal at day 57).

No problem, this is a good question and you have found the correct subsection. Well done and welcome . +1 Both electrons forming a covalent bond need not come one from each atom. One atom may supply them both. This type of bond is called a dative covalent bond. Now what you are referring to was probably in solution. In solution the HCl is fully dissociated (it is a strong acid) to produce H+ and Cl- ions. The lone pair (do you understand lone pairs ?) of the nitrogen in the neutral ammonia and the H+ ion are drawn towards each other to form a dative covalent bond. Does this help?

That is a bit tricky. For coated viruses folks often see seasonality and it is suspected that at lower absolute humidity the viral particles stay infectious for longer (there are various hypotheses as to why, incl. osmotic pressure, staying longer in the air as aerosols etc., but no definitive answer AFAIK). While seasonality have been observed in various coronaviruses, there have been (as you noted) sustained transmission in humid regions. So folks by now assume an at best modest slowdown, but not a sharp decline.

Coronaviruses are RNA viruses. On the RNA strand they encode everything they need to replicate and form the capsids. I have mistyped earlier (ironically i did not proofread) and one of the genes it encodes a proof reading exoribonuclease. It excises mismatched nucleases. Other proteins required for basic processes such as ribosomes are hijacked from the host rather than being encoded in the viral genome.

! Moderator Note You have a thread open for this already.

Just for the avoidance of doubt, steel and iron are basically the same thing when it comes to an application like this. Steel is iron with specific impurities added (mainly carbon). Mild steel is closer to pure iron.

1. Yes, the material must be ferromagnetic. In practice, it means steel (mild steel, more specifically). Other ferromagnetic materials exist, but are harder to obtain. Mild steel, on the other hand, is very common - nails, bolts and many other things. Generally, lower the carbon content in the steel, better its magnetic permeability. Pure iron (like 99.95% pure) would be very good, but you won't find it. Most steel will have like 0.2% carbon or more... Some specifically made alloys can also have very good magnetic properties - like electrical steel (silicon steel). You can find this inside transformers, but you might be disappointed because you will find it in form of thin sheets. Better material (higher magnetic permeability) can make better electromagnets, but it only pays so much to obtain it. It won't have superpowers. You can easily check if a material is ferromagnetic - if a magnet sticks to it it is ferromagnetic and will make an electromagnet. (Brass, copper, bronze, aluminum, and most stainless steel are NOT ferromagnetic). 2. Yes, you can wrap wire around any ferromagnetic material and it will show some magnetic effect. You might be disappointed with the oven pan - as it will make a weak electromagnet. If you make a thin and wide plate and wrap a wire around its perimeter, the effect will be small. Magnetic field lines must close themselves, and if your plate is wide they must go long way all around the plate to the other side - if you force magnetic field lines to 'travel' long way through the air it is hard to make them strong (dense, actually). The magnetic field is the 'happiest' if it can travel through iron most of the time and only make short jumps over the air. A better design would be if you make many small electromagnets (wire around a short bolt) and arrange them side-by-side in a plane to make a plate. You must orientate every other one into the opposite magnetic direction. Magnetic filed lines will 'run' through them from one side to the other side of the plate, taking only short jumps over the air. 3. In addition to the magnetic permeability of the ferromagnetic material, and in addition to the length the magnetic field lines must travel (as said, especially critical is how far they travel through air or other non-ferromagnetic paths), the strength of the electromagnet will be governed by ampere-turns. That is, current in the wire current multiplied by the number of the wire turns. You can choose appropriate wire gauge to adjust the electromagnet to your battery. With thinner wire you will be able to make more wire turns and its resistance will be greater. The current will be smaller (when connected to the battery of some voltage) and the battery will last longer. Of course, a wire can take only so much current so there are limits. Another limit is the ferromangetic material itself - it will only 'allow' magnetic field up to certain strength (in practice, some 1.5 tesla - but you will have hard time to reach even this). All said above is for simple case of DC powered electromagnets (battery). For AC powered electromagnets (or electromagnets where activation/deactivation time is critical), things get more complicated.

Check this out. Radiooooo.com Music from 1900-now, from anywhere in the world (almost). Just click on a decade then a country. http://radiooooo.com/# To change the song, change the mood setting- slow fast weird. It's in Beta mode so it's not perfect.

Maybe a better question might be to ask who formed the earth and the environment so that the humans could occupy it in the beginning. If you are thinking of going back further than that, then maybe asking what or who had the consciences to understand and be able to form life in the beginning, even if that boils down to matter, atoms, fluids etc, who formed them and if the big bang enters the equation, who created and caused that ?