Question

what happens to the matter when fuel burns?
how does the addition of btb help us make sense of matter changes taking place during this reaction? how does the addition of the infra red thermometer help us make sense of energy transfers taking place during this reaction?
btb changes color when interacted with co2 so it helps see if co2 concentrations increase in the hair while burning the ethanol
btb changed its color due to co2 which means the change of co2 in the air means burning ethanol could make lethal doses of co2
the btb solution changes color from blue to yellow to indicate an increase in co2 in the air while the ethanol burns
the color change in the btb helps us determine what changes occur for the carbon
the color change in the btb shows the change of co2 when the ethanol was burned. the rtr turned
it helps us see how much energy is being released and confirm that a chemical
its helps show how much energy is being release and actually let us know that a

Explanation:

When fuel (like ethanol) burns, it undergoes a chemical reaction (combustion). The matter (fuel + oxygen) is transformed: fuel (e.g., ethanol, \( \text{C}_2\text{H}_5\text{OH} \)) reacts with oxygen (\( \text{O}_2 \)) to form carbon dioxide (\( \text{CO}_2 \)) and water (\( \text{H}_2\text{O} \)) (and energy). Mass is conserved (Law of Conservation of Mass), so atoms rearrange, not disappear.

• BTB (Bromothymol Blue) Role: BTB is a pH indicator that changes color (blue to yellow) in acidic conditions. \( \text{CO}_2 \) dissolves in water (or the BTB solution) to form carbonic acid (\( \text{H}_2\text{CO}_3 \)), lowering pH. The color change (blue → yellow) signals \( \text{CO}_2 \) production, showing that carbon - containing fuel is being converted (matter change: carbon in fuel becomes \( \text{CO}_2 \)).

• Infrared Thermometer Role: Combustion is exothermic (releases energy as heat). The infrared thermometer measures temperature increase, indicating energy transfer (chemical energy in fuel → thermal energy). This confirms energy is released during the reaction, supporting the idea of energy transformation in the chemical change.

Answer:

What happens to the matter when fuel burns?

When fuel (e.g., ethanol) burns, it undergoes combustion (a chemical reaction). The fuel (containing carbon, hydrogen, etc.) reacts with oxygen (\( \text{O}_2 \)) from the air. Atoms in the fuel and oxygen rearrange: carbon in the fuel forms carbon dioxide (\( \text{CO}_2 \)), hydrogen forms water (\( \text{H}_2\text{O} \)), and energy (heat, light) is released. Matter is conserved—atoms are not created or destroyed, just rearranged into new substances (\( \text{CO}_2 \), \( \text{H}_2\text{O} \), etc.).

How does BTB help make sense of matter changes?

BTB (Bromothymol Blue) is a pH - sensitive indicator. When fuel burns, it produces \( \text{CO}_2 \). \( \text{CO}_2 \) dissolves in the BTB solution (or surrounding water) to form carbonic acid (\( \text{H}_2\text{CO}_3 \)), which is acidic. BTB changes color from blue to yellow in acidic conditions. This color change shows that \( \text{CO}_2 \) (a new substance) is being produced, confirming that the fuel’s carbon - based matter is being transformed into \( \text{CO}_2 \) during the reaction.

How does the infrared thermometer help with energy transfers?

Combustion is an exothermic reaction (releases energy as heat). The infrared thermometer measures the temperature of the surroundings (or the reaction area). A temperature increase (detected by the thermometer) shows that chemical energy stored in the fuel is being transferred to thermal energy (heat), confirming energy transfer during the reaction.