Endothermic<span> Reaction??? </span>
Answer:
Explanation:
A solar collector is a device that absords Sun's heat energy to heat air or water. It is majorly used for heating purpose, and do not generate electricity directly.
The flow tubes and collector plate are black in color so as to increase the intensity of heat generated by the collector. A black body is a good absorber of heat, it absorbs most heat directed to the collector. Also, a black body is a good radiator of heat, the heat absorbed is rediated to the appropriate channels for the heating of water or air molecules. The black color increases the efficeincy and percentage of solar energy absorbed by the collector.
If a reflective color is used (e.g white), major percentage of the incident heat would be reflected. This would decrease the efficiency of the solar collector.
When a specific amount of energy is emitted when excited electrons in an atom in a sample of an element return to the ground state, this emitted energy can
<span>be used to determine the "identity of the element".</span>
Explanation:
The given data is as follows.
= 10 mM =
M
= 750 ml,
= 5 ml
= ?
Therefore, calculate the molarity of given NaCl stock as follows.


= 1.5 M
Thus, we can conclude that molarity of given NaCl stock is 1.5 M.