Question

A common antacid contains the acid-neutralizing agent sodium hydrogen carbonate. Write the chemical formula for sodium hydrogen carbonate.

Answer 1

Sodium hydrogen carbonate has:
$sodium \: ion ( {Na}^{+}), hydrogen \\ ion ( {H}^{+}), and \: carbonate \\ ion ( {CO3}^{2-})$
The + from Na+ and + from H+ makes 2+, and therefore the 2- from CO3 evens the charges to neutral.

Not to be confused with Sodium Carbonate, (Na2CO3), which lack an H, Sodium Hydrogen Carbonate is sometimes shortened to just Sodium Bicarbonate. It is used in the kitchen (cooking) as "baking soda."

Formula: NaHCO3