Nuclear fission works by a neutron (a tiny particle) hitting an atom of uranium-235, causing it to split into two new atoms, both of which are smaller.

These new atoms can't be used in a nuclear reaction but still have a lot of mass (only a teeny amount is turned into energy) so the spent fuel rod still has a mass which is almost identical to the "new" rod, hence a lot of waste being produced after the reaction because these new atoms are quite unstable in their own right.

The water table and aquifers can be found underground. Exactly where and how good they are will depend on a lot of things, such as rainfall, underground river flows, types of rocks and how porous they are (how easy it is for water to move through the rocks).

There's a lot that goes into it and the best place to dig would be where the rock or soil is easiest to shift and the most water is closest to the surface.

A fluid is anything that can flow. A liquid is a type of fluid (another type is a gas, probably a plasma as well).

So liquid is a subgroup of the states of matter that are fluid.

Fluids (liquids and gases) form layers based on their density, which we find by dividing their mass (how much stuff there is and how heavy it is) by their volume (how much space they take up).

Gases (and indeed most substances) expand as they get hotter; the amount of stuff, and therefore mass, stays the same but the volume increases - therefore the density falls.

Hotter air is thus less dense than colder air and so it rises, causing the colder, more dense air to fall.

As you get higher in the atmosphere, there's more space to occupy (think concentric circles; they get bigger and bigger as the radius increases). With more space to occupy, again the density is going to decrease as the gases spread out. This also causes them to cool down (Boyle's Law, Charles' Law and the ideal gas law are a bit beyond a 5 year old though).

Also most of the sun's energy that comes to earth hits the surface (gas molecules are TINY so most of the sun's rays will miss them and some of the ones that do hit them bounce off) so the surface warms up far more than the atmosphere does. The surface then loses heat to the atmosphere. Since this heat starts at ground level, the air closest to the ground has more chance to absorb it and therefore the air closer to the ground will be hotter than air higher up.

The Goldilocks zone will depend on the star's temperature and therefore how much its energy output is, so yes over time it will shift. To take an extreme example, our Sun's late life stage will see it expand and swallow up the earth; clearly we will no longer be in the zone when that happens.

So yes, the zone will shift but the lifespan of a star is so long that it won't change on a human (or even humanity's) timescale for most stars.

It can. Carbon can actually form a quadruple bond with itself but the fourth bond is extremely weak because of the way the hybrid orbitals are arranged. Strength of bond depends on orbital overlap and these fourth orbitals are pointing in opposite direction (think the hydrogens in acetylene) so there's little overlap.

So C2 isn't a very stable molecule; it's also not a particularly interesting one since it's literally just two carbons.

Yes, while it is above the glass transition temperature it will be rubbery and become glassy again when it cools.

Usually polymers go through a glass transition at a certain temperature (called, surprise, surprise, the glass transition temperature). Below that they are hard and rigid (like glass), above that they become rubbery. Smaller molecules, called plasticisers, can be added which will artificially decrease the glass transition temperature (e.g. PVC tubing compared to uPVC used in windows and doors). Since these are small molecules they are more volatile and once gone, the polymer will become glassy (those PVC tubes stiffening with age). So my guess would be that the plasticisers in the bag have evaporated, causing the polymer to transition from rubber to glass despite the increase in temperature.

Most of cabbage is cellulose, which we tend to call fibre. Our bodies can't digest it so it passes through our system and is pooped out.

Chocolate bars are high in sugar and fat, things our bodies absorb very well so, all other things being equal, you retain far more mass from the chocolate bar than from the cabbage.

The "lost money" was the value of their shares in companies. Shares are "worth" what somebody is willing to pay for them so their "loss" is what they would get for selling them now versus what they would have got for selling them twelve months ago.

Nobody has gained at the moment but buyers WOULD "gain" if these shares were to be sold now, as they'd be cheaper than they used to be. It's unlikely, though, that these shares will become available as rich people tend not to sell at the bottom of the market.

Treatments are more profitable than cures and there are a lot of companies earning a lot of money with people paying for life-long treatment instead of a one-time cure.

Banks receive money from savers and pay them an interest rate. They lend that money to borrowers at a higher rate, giving them their profit margin. Over time this difference in the rate helps them to build up reserves (some of which a bank will pay to its shareholders; a building society or credit union can decrease the difference in rates instead) which they can also lend to borrowers. The reserves will obviously need to be sufficient in case that everyone decided to get their money back at the same time, which is why they offer a better rate on fixed-term savings (1 year, 2 years) where you can't access your money at all during that term, ensuring that they don't need to worry about suddenly having to return it.

Water has a density of 1kg/L. Since soda is mostly water (with stuff dissolved in it) it will have a similar density, thus your 1.5kg for 1.5L. Some of the ingredients will affect that, particularly the carbon dioxide as it escapes from the solution as a gas, but it should still have a density close to 1.

The effect comes from the pressure exerted: the force divided by the area it acts over. The tip of a bullet has a very low area thus a very high pressure because all the force acts through a single point. The recoil is an equivalent force but the gun is held in one or both hands so the force pushes up the arms to the body and acts against your whole body mass, thus dissipating its effect.

The closer to the equator you are, the more equal lengths of day and night are all year round. California is much closer to the equator than the UK is.

There's likely still a copy in the sender's sent items folder, unless they routinely empty that.

To the best of our knowledge, uranium has the highest atomic number of naturally occurring elements (Z=92). Anything above that (93 - 118) was synthesised in a particle accelerator. There's no reason why we can't continue to do this with higher and higher atomic numbers but most of the nuclei are so unstable that they only exist for a fraction of a second before disintegrating, so they have no practical uses. There is a hypothesised "island of stability" where some semi-stable nuclei could exist with longer half-lives but again it's unlikely that anything will exist long enough to be useful.

So we MIGHT find some new elements out in space but they'd almost certainly be synthesised by an alien race and be extremely short-lived.