Nitrogen has an atomic mass of 14.007 amu. nitrogen has two common isotopes. one has a mass of 14.003 amu and relative abundance of 99.632%.
a) what is the percent abundance of the other isotope?
b) what is the mass of the other isotope?
i know how to find average atomic mass, but my chem teacher hasn't shown is anything like this and it's on our study guide. how do i do this and how can i remember for the test?

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.