A scientist spilled a few drops of dilute hydrochloric acid (hcl) on a lab table. for safety purposes, the scientist sprinkled some baking soda (nahco3) onto the spill. which observation would provide the best evidence that a chemical reaction occurred

Hello!

The observation that would provide the best evidence that a chemical reaction occurred is that The baking soda and hydrochloric acid combined, and bubbles formed.

When baking soda (NaHCO₃) and Hydrochloric Acid (HCl) combine, the following reaction happens:

NaHCO₃ + HCl → NaCl + H₂O + CO₂ (g) ↑

The gaseous Carbon Dioxide (CO₂) generated in this reaction is the responsible for the bubbles. The releasing of this gas is an evidence that a chemical reaction occurred between NaHCO₃ and HCl.

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