Answer:
element
Explanation:
elements consist of pure substances
Heating a substance causes molecules to speed up and spread slightly further apart, occupying a larger volume that results in a decrease in density. Cooling a substance causes molecules to slow down and get slightly closer together, occupying a smaller volume that results in an increase in density.
From: www.middleschoolchemistry.com
Answer:
Explanation:
Electronegativity is a measure of the ability of an atom to attract the electrons when the atom is part of a compound. Electronegativity values generally increase from left to right across the periodic table. The highest electronegativity value is for fluorine.
Answer:
Nitrogen, 
Explanation:
Hello,
This is a clear example of what the ideal gas equation is used for, thus, from its mathematical definition:
One can spell it out in terms of mass and molar mass:
Now, solving for the molecular mass, 
:
Now, by taking into account that the gas is diatomic, the matching gas turns out to be nitrogen.
Best regards.
