A student places 2.0 g of solid sodium hydrogen carbonate (baking soda) into a 20 mL…
CHEMISTRY · Multi-part · AP · Chemistry · Chemical Reactions · Chemical Reactions
Problem
A student places 2.0 g of solid sodium hydrogen carbonate (baking soda) into a 20 mL syringe, adds 5 mL of 1.0 M hydrochloric acid, quickly seals the syringe, and gently mixes the contents. The temperature of the room is 25 °C.
(1) Describe the macroscopic change(s) the student should expect to observe inside the syringe during the reaction.
(2) Explain, in terms of particle rearrangement, why the change(s) you described in part (a) constitute evidence of a chemical reaction rather than a physical process.
(3) Predict whether the plunger of the sealed syringe will move inward, outward, or remain stationary as the reaction proceeds, and justify your prediction without performing calculations.