Answer:
open system
Coffee held in a cup is an open system because it can exchange matter water vapors and energy heat with the surroundings.
A liquid becoming a gas. For instance water (liquid) turns into steam (gas).
Answer:
The symbol of the ion is A^-
Explanation:
Let A be the symbol of the element.
Proton = 17
Electron = 18
Neutron = 20
Since the element has more electrons than protons, it means it has gain electrons.
From the question given,
The difference between the electron and proton = 18 — 17 = 1
So, the element has gain 1 electron.
Therefore the symbol of the ion is A^-
Explanation:
The speed of molecules increases when temperature is increased as it will result in more number of collisions between the molecules. Thus, there will be increase in kinetic energy of molecules and increase in the speed of solvent molecules.
Whereas on decreasing the temperature, the kinetic energy of molecules will decrease. This will result in less number of collisions between the molecules. Therefore, the speed of solvent molecules will slow down.