Answer:
Electrons are always marked negative Hence electronic energy is also always taken as negative. It is because when an electron is at infinite distance from nucleus , there the kinetic energy of that electron can not be calculated. So, it is taken to be zero . ... And thus the energy of electron becomes less negative
Answer:
The number of mole is 1.852moles
Explanation:
To calculate the number of mole, using the formula
n = m/Mm
n - number of mole
m - number of mass
Mm - number of molar mass
The molar mass of Re = 186.207
Then, n = 345g/ 186.207g/mol
n = 1.852mol
Answer:
Mass in an isolated system can neither be destroyed nor created.
Explanation:
