To count the number of valence electrons we look at the electronic configuration and add the electrons form the electronic shell with the highest principal quantum number.
Rb: [Kr] 5s¹ - 1 valence electron
Xe: [Kr] 5s² 4d¹⁰ 5p⁶ - 8 valence electrons
Sb: [Kr] 5s² 4d¹⁰ 5p³ - 5 valence electrons
I: [Kr] 5s² 4d¹⁰ 5p⁵ - 7 valence electrons
In: [Kr] 5s² 4d¹⁰ 5p¹ - 3 valence electrons
Rank from most to fewest valence electrons:
Xe > I > Sb > In > Rb
Gases are compressible because most of the volume of a gas is composed of the large amounts of empty space between the gas particles. Hope this helped!
a) A combound which contains only Carbon and Hydrogen. There are covalent bonds between atoms. Hydrogen form one single bond and Carbon forms four covalent bonds. Carbon bonds can be single, double or triple bonds.
All hydrocarbons are organic compounds, but organic compound can include atoms of other elements.
b) Alkyne has a covalent triple bond between two carbon atoms. Simplest alkyne is ethyne HCCH.
b) Alkane contains only Carbon and Hydrogen and there are single bonds
between atoms. Simplest alkane is methane CH4.
c) An alkene has one double bond between Carbon atoms. Simplest
alkene is ethene H2C=CH2.