What is the balanced equation for the reaction of NaHCO3 with hydrochloric acid (HCl)? 1 NaHCO3 + 1 HCl –> 1 NaCl + 1 CO2 + 1 H2O
The Correct Answer and Explanation is:
The balanced equation for the reaction of sodium bicarbonate (NaHCO3) with hydrochloric acid (HCl) is:
NaHCO3 + HCl → NaCl + CO2 + H2O
This reaction involves the neutralization of an acid by a bicarbonate salt, producing carbon dioxide, water, and a salt as products. It is a common example of a gas-evolution reaction.
To understand why this equation is balanced, let’s analyze the number of atoms present on both sides. The reactants consist of one sodium (Na) atom, one hydrogen (H) atom from hydrochloric acid, one carbon (C) atom, and three oxygen (O) atoms from sodium bicarbonate. On the product side, the sodium chloride contains one sodium and one chlorine atom, the carbon dioxide consists of one carbon and two oxygen atoms, and the water molecule contributes two hydrogen atoms and one oxygen atom. The total count for each element remains unchanged between reactants and products.
The reaction follows a predictable sequence. Hydrochloric acid donates a proton (H⁺) to the bicarbonate ion, resulting in the formation of carbonic acid (H₂CO₃). This intermediate compound decomposes into carbon dioxide and water spontaneously. The sodium ion from sodium bicarbonate remains in solution, combining with chloride ions to form the ionic compound sodium chloride.
This reaction is commonly observed in applications such as baking and pharmaceutical formulations. Baking soda, which is primarily sodium bicarbonate, reacts with acidic ingredients like lemon juice or vinegar to release carbon dioxide, leading to the expansion of dough or batter. Similarly, antacids containing bicarbonates neutralize excess stomach acid through this reaction, relieving symptoms of acidity. Understanding this reaction also provides insight into acid-base chemistry, buffering systems, and equilibrium concepts fundamental to many biological and industrial processes.
