Ca.
Hydrogen and Carbon combined
Zn = zinc which is a metal, not a carbon atom
Cl=chlorine, just not a carbon atom
Sn isn’t a carbon atom.
I Am positive that it is Ca because Ca means carbon
same family or group called Alkali metals
Answer:
Helium
Explanation: The real gas that acts most like an ideal gas is helium. This is because helium, unlike most gases, exists as a single atom, which makes the van der Waals dispersion forces as low as possible. Another factor is that helium, like other noble gases, has a completely filled outer electron shell.
Answer:
a) located in the outermost energy level.
Explanation:
A valence electron is an electron in the outer shell associated with an atom, and that can participate in the formation of a chemical bond if the outer shell is not closed; in a single covalent bond, both atoms in the bond contribute one valence electron in order to form a shared pair.
Hope this helped!