What is observed when 2 mL of dilute hydrochloric acid is added to 1 g of sodium carbonate taken in a clean and dry test tube? Write the chemical equation for the reaction involved.

A brisk effervescence would be observed if HCl is added to Na₂CO₃ due to the evolution of CO₂ gas.

$Na_2CO_3 + HCl → NaCl + H_2O + CO_2$

(Extra information: HCl is an acid and sodium carbonate is a base. When an acid and a base react they form salt and water. This is called a neutralization reaction. )