Answer:
electron sea model for metals suggest that valence electrons drift freely around the metal cations.
Explanation:
Explanation: In electron sea model, the valence electrons in metals are delocalized instead of orbiting around the nucleus. ... These electrons are free to move within the metal atoms. Thus, we can conclude that the electron sea model for metals suggest that valence electrons drift freely around the metal cations.
Answer:
The temperature is always lower.
Explanation:
The temperature is always lower at the end of the state as compared to beginning of the state. We can see in the given data, the temperature is higher at the beginning i. e. 140 degree Celsius but with the passage of time, the temperature of a state decreases constantly and the temperature at the end is lower i. e. 20 degree Celsius. So we can conclude that the temperature is always lower.
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.
It will be the Displacement method