Cold packs are used to treat minor injuries. some cold packs contain nh4no3(s) and a small packet of water at room temperature before activation. to activate this type of cold pack, the small packet must be broken to mix the water and nh4no3(s). the temperature of this mixture decreases to approximately 2°c and remains at this temperature for 10 to 15 minutes.

state the direction of heat flow that occurs when the activated cold pack is applied to the body.
identify both types of bonds in the nh4no3(s).

"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."

a rain shadow is a dry region of land on the side that is protected against the prevailing winds of a mountain range. the prevailing winds are the winds that occur most of the time in a particular place of the earth

prevailing winds carry air toward the mountain range. as the air rises up over a mountain range, the air cools, water vapor condenses, and clouds form. on this side of the mountains, called the windward side, precipitation falls in the form of  rain  or snow. this dry air produces a  rain shadow.