When 2.50 g is burned then in oxygen then 1.25kj of heat is produced.
Answer:
a solution color becoming less intense due to dilution- is not an evidence of a chemical reaction
bubbles (gas formation) - evidence of a chemical reaction
explosion or fire - evidence of a chemical reaction
changes in color- evidence of a chemical reaction
precipitation- evidence of a chemical reaction
changes in temperature - evidence of a chemical reaction
a solid liquifying - is not an evidence of a chemical reaction
solution colors mixing - is not an evidence of a chemical reaction
Explanation:
A chemical change is not easily reversible and yields new substances. It is often accompanied by a loss or gain of heat.
In the answer section, i have shown some evidences that lead us to conclude that a chemical reaction has taken place. The occurrence of a chemical change often goes with the formation of new substances as earlier stated and any of these signs may accompany the process.
For instance, when a metal is dropped in dilute acid solution, bubble of hydrogen gas indicates that a chemical reaction has taken place.
Refer to attachment for your answer
answer:
in plants
Transport manufactured food from the leaves to others parts of the plant
Facilitates gaseous exchange through the stomata in the leaves to other parts of the plant
in animal
Exchange of respiratory gases across respiratory services
Excretion of nitrogenous waste in some unicellular organisms
Explanation:
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