Boiling water, steam from a cup of tea and ice melting
Elements with three p-electrons....
That would be N, P, As, Sb, and Bi -- elements in group 15
For example, energy diagram showing "empty" orbitals up through the 3p.
.....3p __ __ __
3s __
.....2p __ __ __
2s __
1s __
Energy diagram of phosphorous showing three unpaired electrons in 3p-sublevel
.....3p ↑_ ↑_ ↑_
3s ↑↓
.....2p ↑↓ ↑↓ ↑↓
2s ↑↓
1s ↑↓
According to Hund's rule, the electrons singly occupy the p-orbitals, and all have the same spin.
<span>density is defined as mass per volume.. so 94 mL makes no sense.</span>
Answer:
B
Explanation:
The normal way to express an energy reaction is to put the energy on the left. Then you can make a rule.
- If the energy on the left is plus then the reactants require energy. The reaction is endothermic -- energy is taken from the environment.
- If the energy is minus when it is on the left. then the reactants give up energy. The reaction is exothermic and energy is given to the environment.
2CO(g)+O2(g) - energy --> 2CO2(g)
Exothermic
