1. Naturally occurring chlorine molecules, Cl2, have masses of 70, 72 and 74 amu as seen in the mass spectrum above. They occur in the percentages 56.25%, 37.50% and
6.250% respectively. Use this data to calculate the average atomic mass of chlorine
atoms and to find the relative abundance of 35Cl and "CI isotopes.

out of these options:

ability to burn paper

pure sodium reacting violently with water

the boiling point of water

helium does not tend to react with anything

i would say this is a physical property:

helium does not tend to react with anything

why? :

i said helium does not tend to react with anything because well, it reacts to ! but ability to burn paper, pure sodium reacting violently with water, & the boiling point of water are chemical or

physical properties: the properties of a substance that can be observed without changing the chemical makeup of the substance

chemical properties: properties of a substance relating to the chemical nature and reactivity of the substance

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.