Answer:
The order of elements by volume-fraction (which is approximately molecular mole-fraction) in the atmosphere is nitrogen (78.1%), oxygen (20.9%), argon (0.96%), followed by (in uncertain order) carbon and hydrogen because water vapor and carbon dioxide, which represent most of these two elements in the air, are variable.
I copied and pasted but I hope this information is helpful :)
Alkali metals have the lowest electronegativities, while halogens have the highest.
Elements and compounds are both examples of pure substances. Compounds are substances that are made up of more than one type of atom. Elements are the simplest substances made up of only one type of atom. i hope that helps:)
Positive because it keeps going ok
Answer: 10.99
Explanation: because you take the Cao 13.9 and take CO2 which is 10.99 and it makes 24.8 . Which is CaCO3.
