Answer:
<em>ii</em><em> </em><em>and</em><em> </em><em>iv</em><em> </em>
Explanation:
atomic mass is the sum of protons and neutrons
protons ( postively charged) usually have the same number like electrons( negatively charged)
Answer:
atoms have no overall charge. this is because they contain equal numbers of positive protons and negative electrons
Hi!
In collision theory, for a chemical reaction to occur - there must be <em>sufficient </em>energy to break down chemical bonds.
We call this the activation energy, as it's the energy needed to <em>activate </em>a chemical reaction!
Hopefully, this helps! =)
Mass would be the amount of matter an object contains.
Explanation:
about 78 % of the air is nitrogen and 21% is oxygen . These two gases can be seperated by fractional distillated of liquid air . Air is filtered to remove dust ,and then cooled in states until it reaches -200'C at this tempereture it is liquid . The air has been liquefied. And after a distillation process you can obtain nitrogen from a mixture of nitrogen and oxygen .