Answer:
C.
Explanation:
The sun is directly overhead at noon on the equator on the first day of spring, and on the first day of fall. You would have to be less than 23.5 degrees above or below the equator to have the Sun pass directly overhead. Therefore, it never occurs in the continental US.
Answer:
A. The increase in the mass of the magnesium oxide was due to oxygen atoms in the air.
Explanation:
Burning occurs in the presence of oxygen. A chemical combination occurs between Mg and O in that the atom of magnesium attracts one another.
Mg + O₂ → MgO
Starting with the magnesium, on reacting with oxygen a new compound forms. This is why there is mass increase in the MgO compared to the starting material.
Answer: 
Explanation:
Lattice energy : It is defined energy released when ions combine together in a gaseous phase to form a compound. it is energy possessed by the crystal lattice of a compound. Denoted by symbol 
.
, energy is absorbed while forming of the lattice
, energy is release while forming of the lattice
One mole of sodium ion when combines with one mole chloride ion release 786 kJ of energy.
