What is the definition of light in one sentence

The dictionary definiton of light is:

the natural agent that stimulates sight and makes things visible.

I'll paraphrase/give a scientific definition:

Light is made of subatomic particles called photons, which jumps electron shells when they're excited, effecting the electromagnetic spectrum, creating visible light.

Hope this helps. Might not as I'm not perfect on this topic yet.

in theory, limestone is composed principally of the compound calcium carbonate - caco3, but in reality this compound is deposited in conditions involving a number of other compounds as impurities so it ends up being a mixture of many compounds.

hope this : -)

tony (lordcaos066)

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"