The water in an aquarium is warmed by a heater located under the gravel in the bottom of the aquarium. Explain how the energy is transferred to the gravel.

Explanation:

Proper placement of the aquarium heater will assure that the tank is In your home aquarium, the best location for placing a heater is near the maximum water flow,  heater is what quickly and evenly disperses heated water throughout  instead of one 200 watt heater, use a 100-watt heater at each end.

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Explanation:

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."

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