These are the formulas of each compound mentioned:
1) Hydrogen chloride: HCl
2) Sodium hydrogen carbonate: NaHCO3 , this is also known as sodium bicarbonate. The number 3 to the right of O is a subscript.
3) Sodium chloride: NaCl
4) Carbon dioxide: CO2. This is also known as carbon anhydride. The number 2 to the right of O is a subscript.
5) Water: H2O. The number 2 to the right of H is a subscript.
The the chemical equation is:
HCl + NaHCO3 → NaCl + CO2 + H2O
Check the balance
element left side right side
H 1+1 = 2 2
Cl 1 1
Na 1 1
C 1 1
O 3 2+1 = 3
Then, given that the number of each element on the left side is equal to the number of elements in the right side, the equation is balanced.