BioMedical Admissions Test (BMAT) 2025 – 400 Free Practice Questions to Pass the Exam

The production of a "squeaky pop" sound when a metal reacts with dilute acid is indicative of the release of hydrogen gas. This distinctive sound occurs when hydrogen gas is ignited, forming a small explosion as it is produced in sufficient quantity during the reaction.

Aluminum is known to react with dilute acids, such as hydrochloric acid, to produce aluminum chloride and hydrogen gas. The reaction is vigorous enough to generate a significant amount of hydrogen, which can lead to the characteristic "squeaky pop" sound when a small amount of this gas is ignited.

While iron, zinc, and magnesium can also react with dilute acids to produce hydrogen gas, the intensity and manner of their reactions differ. Magnesium generates more hydrogen gas rapidly and may produce a louder sound, but the classic "squeaky pop" is often attributed to aluminum specifically due to the nature of its reaction when unprotected by an oxide layer.