Answer: 12.18 u
Explanation: The average atomic mass of an element is calculated by taking the weighted average of the atomic masses of its stable isotopes.
In other words, each stable isotope will contribute to the average mass of the element proportionally to its abundance.
Answer:
B. Intermolecular forces are hard to overcome
Explanation:
A high boiling point indicates greater inter molecular forces between the molecules of the substance. Inter molecular forces is the force of attraction between the molecules of the substance, which has to be overcome or broken before the substance boils. Example, when water boils, the water molecule (H₂O) will be broken into hydrogen molecule and oxygen molecule.
Therefore, a high boiling point temperature indicates that intermolecular forces of the substance are hard to overcome.
B. Intermolecular forces are hard to overcome
