EVERYDAY SCIENCE

Detailed explanation-1: -Bromothymol blue (BMB) is an indicator dye that turns yellow in the presence of acid. When carbon dioxide is added to the solution, it creates carbonic acid, lowering the pH of the solution. BMB is blue when the pH is greater than 7.6, green when the pH is between 6-7.6, and yellow when the pH is less than 6.

Detailed explanation-2: -BTB is an acid indicator; when it reacts with acid it turns from blue to yellow. When carbon dioxide reacts with water, a weak acid (carbonic acid) is formed (see chemical reaction below). The more carbon dioxide you breathe into the BTB solution, the faster it will change color to yellow.

Detailed explanation-3: -Bromothymol blue solution (BTB), used here to test for the presence and relative concentration of carbon dioxide, is an acid/base indicator that measures the pH range from 6.0 (yellow) through green to 7.6 (blue).

Detailed explanation-4: -Expert Answer Due to the formation of H₂CO₃, the solution becomes acidic and BTB (bromothymol blue) turns yellow under acidic conditions. Therefore, the color of the solution appears yellow when BTB was exposed to the CO₂ gas.

Detailed explanation-5: -Bromothymol blue (BTB) is a chemical that turns yellow in the presence of carbon dioxide.