El agua oxigenada (H2O2) es una sustancia muy utilizada en medicina y cosméticos. Se descompone mediante la acción enzimática de la catalasa, produciendo agua y oxígeno molecular (O2). Su poder desinfectante se debe a la acción del oxígeno producido. Si para desinfectar una herida de necesitan 25 moles de O2 ¿cuántos mL de agua oxigenada se requieren emplear? Considera que la densidad del H2O2 es 1.45 g/mL (2 ptos). H2O2 (l) > O2 (g) + H2O (l)

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

the increase of protons   hope this

it is the most commonly accepted one