Auroras occur when ions from the Sun strike air molecules, causing them to give off bright colors of light.-google
The equation is:4Al+3O2----2Al2O3
When we convert the given mass in grams and volume in liters to m/v percent, we recall that m/v percent is expressed as grams/100 milliliters. In this case the expression becomes (50 grams/ 2500 L)*(0.1L/100ml), that is equal to 0.002 grams/ 100 mL. Hence the the concentration is equal to 0.2 m/v percent.
J.J. Thomson's experiments with cathode ray tubes showed that all atoms contain tiny negatively charged subatomic particles or electrons. ... Rutherford's gold foil experiment showed that the atom is mostly empty space with a tiny, dense, positively-charged nucleus.
The answer is: when the aim is to show electron distributions in shells
An orbital notation is more appropriate if you want to show how the electrons of an atom are distributed in each subshell. This is because there are some atoms that have special electronic configurations that aren't obvious in just written configurations.
