Where are the elements that have the same valence electrons found in the periodic table

Look at the reaction below: ca(hco3)2 --> caco3 + co2 + h2o first, balance the reaction. once balanced, use dimensional analysis or another method to find out how many moles of carbon dioxide will be produced if we start with 16.5 moles of calcium bicarbonate (calcium hydrogen carbonate). = mol of co2 number needs to be reported to three significant figures.

Which of the following is always a reactant in a combustion reaction? oxygen nitrogen hydrogen carbon

__can be defined as which velocity changes