Which periodic family has a full outermost valence shell and rarely reacts with other elements? Alkali metals
Alkaline earth metals
Halogens
Noble gases

What are the first three quantum numbers for the electrons located in subshell 2s?

How have the greenhouse gasses increased from the year 2000 to 2018

A4.86 g piece of metal was placed in a graduated cylinder containing 15.5 ml of water. the water level rose to 17.3 ml. what is the density of the metal. i need the steps of how to solve it to so i can use a formula to work out other problems.