during an experiment, mr. lehman tells his students to be alert for signs that an endothermic reaction is…

during an experiment, mr. lehman tells his students to be alert for signs that an endothermic reaction is happening. which of the following scenarios would his students most likely observe? a test tube becomes cool to the touch. a liquid appears to glow. a new odor comes from a beaker. a solid forms from a mixture of solutions.

during an experiment, mr. lehman tells his students to be alert for signs that an endothermic reaction is happening. which of the following scenarios would his students most likely observe? a test tube becomes cool to the touch. a liquid appears to glow. a new odor comes from a beaker. a solid forms from a mixture of solutions.

Answer

Brief Explanations:

An endothermic reaction absorbs heat from the surroundings. When a test - tube becomes cool to the touch, it indicates that heat is being absorbed from the surroundings into the reaction system, which is a sign of an endothermic reaction. A liquid glowing is usually related to chemiluminescence or other non - endothermic processes. A new odor coming from a beaker is more related to the formation of new substances with characteristic smells, not necessarily endothermic reactions. A solid forming from a mixture of solutions is a precipitation reaction, which may or may not be endothermic.

Answer:

A. A test tube becomes cool to the touch.