revise.txt

chromatography is separation of solution containing many molecules
hard water contains either magnesium or calcium ions.
pernament hard water cantains CaSO / MgSO /CaCl / MgCl
temporary hard water contains CaHCO / MgHCO
softening hard water: ion exchange / boiling / adding sodium carbonate
fluoridation strengthens tooth enamel, causes kidney problems
every solid liquid or gas is made from atoms
element is made out of only 1 atom
periodic table : groups(veritcal), Periods(horizontal)
sodium flame colour is orange
copper flame colour is green
potassium flame colour is lilac
lithium flame colour is red
calcium flame colour is red
4M + O2 ==> 2 M2 O
red blood cells are biconcave in shape
blood enters the heart at the vena cava and pulmonary vein
arteries have a small lumen, to hold pressure
atherosclerosis is build up of plaque in the arteries
stroke is a blocage of blood to the brain
photosynthesis = water + carbon dioxide = glucode + oxygen
respiration uses oxygen and glucose to make ATP and carbon dioxide
Babies have around 100 more bones than adults
The Eiffel Tower can be 15 cm taller during the summer
20% of Earth's oxygen is produced by the Amazon rainforest
Some metals are so reactive that they explode on contact with water
A teaspoonful of neutron star would weigh 6 billion tons
It is physically impossible for you to lick your elbow.
Like fingerprints, everyone's tongue print is different.
Your heart beats over 100,000 times a day.
It takes approximately 12 hours for food to entirely digest.
A sneeze travels out your mouth at over 100 m.p.h.
There are 62,000 miles of blood vessels in the human body – laid end to end they would circle the earth 2.5 times
At over 2000 kilometers long, The Great Barrier Reef is the largest living structure on Earth
The risk of being struck by a falling meteorite for a human is one occurrence every 9,300 years
A thimbleful of a neutron star would weigh over 100 million tons
A typical hurricane produces the energy equivalent of 8,000 one megaton bombs
Blood sucking hookworms inhabit 700 million people worldwide
The highest speed ever achieved on a bicycle is 166.94 mph, by Fred Rompelberg
We can produce laser light a million times brighter than sunshine
65% of those with autism are left handed
The combined length of the roots of a Finnish pine tree is over 30 miles