Answer:
The kilogram is the standard unit of mass.
False, that only applies to water as far as I know, but I know for a fact that gold does not melt at 0 degrees Celsius
Ultraviolet Rays ( UV rays) can harm humans because they can cause sunburn, and skin cance if you stay out in the sun for too long.
Answer:
Molecule
Explanation:
molecule of the substance. You can break the molecule down further, into the atoms that make it up, but those don't have the properties of the original 'compound'.
Here's an example:
-- Sodium is a soft, slippery metal, that explodes when water touches it.
-- Chlorine is a poisonous green gas.
When an atom of Sodium and an atom of Chlorine combine, they make one molecule of a substance called "Sodium Chloride". That's SALT ! It isn't green, it isn't a gas, it isn't poisonous, it isn't soft and slippery, and it doesn't explode when water touches it.
elements:
calcium : for strong bones
Iron : maintaining haemoglobin for metabolism
compunds
sodium chloride : to maintain blood pressure and other life processes
Adenosine Triphosphate: for metabolism, to maintain rate of inhalation and exhalation of oxygen and to supply energy
Mixture:
I) gasoline : used as fuel
ii) cement : used in construction