what happens to water molecule when it is exposed at low temperature?
When water is a liquid, it has a random structure (the molecules have not specific structure or distance between molecules).
When water is frozen it forms a rigid structure, due to the spacing of the molecules, which will be greater than liquid water, it will expand, if you freeze a full bottle of water, it will expand and may even break the bottle, this is very clear with milk.
Milk is mostly water, as it freezes it can break the glass bottle.
This explains why ice floats on water, it is less dense and there are fewer molecules per volume.
“A towel, it says, is about the most massively useful thing an interstellar hitchhiker can have. Partly it has great practical value. You can wrap it around you for warmth as you bound across the cold moons of Jaglan Beta; you can lie on it on the brilliant marble-sanded beaches of Santraginus V, inhaling the heady sea vapors; you can sleep under it beneath the stars which shine so redly on the desert world of Kakrafoon; use it to sail a miniraft down the slow heavy River Moth; wet it for use in hand-to-hand-combat; wrap it round your head to ward off noxious fumes or avoid the gaze of the Ravenous Bugblatter Beast of Traal (such a mind-bogglingly stupid animal, it assumes that if you can’t see it, it can’t see you); you can wave your towel in emergencies as a distress signal, and of course dry yourself off with it if it still seems to be clean enough.
More importantly, a towel has immense psychological value. For some reason, if a strag (strag: non-hitch hiker) discovers that a hitch hiker has his towel with him, he will automatically assume that he is also in possession of a toothbrush, face flannel, soap, tin of biscuits, flask, compass, map, ball of string, gnat spray, wet weather gear, space suit etc., etc. Furthermore, the strag will then happily lend the hitch hiker any of these or a dozen other items that the hitch hiker might accidentally have “lost”. What the strag will think is that any man who can hitch the length and breadth of the galaxy, rough it, slum it, struggle against terrible odds, win through, and still knows where his towel is is clearly a man to be reckoned with.”
Matter is anything that has mass and occupies space. The flame itself is a mixture of gases (vaporized fuel, oxygen, carbon dioxide, carbon monoxide, water vapor, and many other things) and so is matter. The light produced by the flame is energy, not matter. The heat produced is also energy, not matter.
Baryonic matter is matter composed mostly of baryons (by mass), which includes atoms of any sort (and thus includes nearly all matter that we may encounter or experience in everyday life, including our bodies).
Non-baryonic matter, as implied by the name, is any sort of matter that is not primarily composed of baryons. This might include such ordinary matter as neutrinos or free electrons; however, it may also include exotic species of non-baryonic dark matter, such as supersymmetric particles, axions or black holes.
The distinction between baryonic and non-baryonic matter is important in cosmology, because Big Bang nucleosynthesis models set tight constraints on the amount of baryonic matter present in the early universe.
Oil is heavier than water, one molecule of oil weighs (depending on the oil, it can have hundreds of carbons and many other organic molecules) much more than a single molecule of H2O! However, one must consider density.
Water is far more dense than oil, i.e. there are more molecules of water per unit volume than oil!
This means it will float on water, even though water is “lighter”.
This also explains why ice floats on water (think icebergs and ice in drinks; as you freeze water, the molecules take up more space, hence when you freeze a bottle of water, it will expand and sometimes break, the same effect can be seen with milk — it is, after all nearly all water).
This fact can be extrapolated from the phase diagram due to the negative slope of the solid-liquid line which is unique to water.
This means you have the same amount of water, but it is of a larger volume and hence it will float as the density has decreased!
Remember, weight can have very little to do with density!
My GCSE Chemistry exam is on the 26th. I still don't understand Empirical Formula or Relative Atomic Mass, can you help explain it in a way that won't blow my not-so-chemically-inclined mind? thanks :)
It’s one of the easier stoichiometric calculations.
mass in grams of the elements in question
relative atomic mass of the elements in question
number of moles of the elements in question (mass divided by relative atomic mass)
divide throughout by the lowest number from (3).
I don’t know about you, but I think of it as a table and do the calculations from (1) to (4) by visualizing the table.
Hey, I just started a tumblr about energy drinks and I was wondering if you have any information about the chemistry behind energy drinks? Like the energy blends of caffeine and taurine and stuff like that.
There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved. ~ On the Origin of Species, Charles Darwin
Scientists are hoping to gain new insights into the mysteries of ageing by sequencing the genome of a 17-year-old girl who has the body and behaviour of a tiny toddler.
Brooke Greenberg is old enough to drive a car and next year will be old enough to vote — but at 16lb in weight and just 30in tall, she is still the size of a one-year-old.
Until recently she had been regarded as a medical oddity but a preliminary study of her DNA has suggested her failure to grow could be linked to defects in the genes that make the rest of humanity grow old.
If confirmed, the research could give scientists a fresh understanding of ageing and even suggest new therapies for diseases linked to old age.
Oh, and along with “arsenic and mercury”, antimony is one of the most deadliest elements on the periodic table.
Misguided doctors in the past used to prescribe it as medicine, and one such patient who was prescribed antimony for his depression and fever was Wolfgang Amadeus Mozart. He died soon after at 35. There are, hence, speculations that Chemistry might have been his undoing.