In a reaction, molecular entity that is formed from the reactants. For example, consider this hypothetical stepwise reaction: A + B → C + D.
There's nothing following?
Explanation :
In thermodynamics, a system is region or part of space which is being studied and observed while the surrounding is the region or space around the system which interacts with the system.
Here in the experiment ,system which is observed is reaction or changes when citric acid and sodium bicarbonate are mixed together. And the mixing is carried out in the calorimeter which serves as a surrounding around the system.
The reason behind the using the calorimeter is measure the energy change occurring during the reaction.
This is due to the hydroxyl group in the alcohol which is able to form hydrogen bonds with water molecules.
Answer:
The answer to your question is: The second option.
Explanation:
Atoms are stable when they gain or lose electrons to have 8 electrons.
They have one valence electron. Noble gases have 8 electrons, not one, If they would have 1 electron they would be extremely reactive.
They have eight valence electrons. This is the right answer, noble gases have 8 electrons that is why they are unreactive.
They have seven valence electrons. If noble gases would have 7 electrons, they would be very reactive.
They have two valence electrons. This option is incorrect, elements that have 2 electrons are reactive like Calcium, Magnesium, etc.
