What is the meaning of valence electron?

Identify one disadvantage to each of the following models of electron configuration: dot structures arrow and line diagrams written electron configurations type in your answer below.

Asolution contains 225 g of sodium chloride, nacl, dissolved in enough water to make a 0.25 l of solution. what is the molarity of the solution?

In 1901, thomas edison invented the nickel-iron battery. the following reaction takes place in the battery. fe(s) + 2 nio(oh)(s) + 2 h2o(l) fe(oh)2(s) + 2 ni(oh)2(aq) how many mole of fe(oh)2, is produced when 5.35 mol fe and 7.65 mol nio(oh) react?