Calcium chloride is used to make pickles. the calcium atom transfers electrons to chlorine atoms, leading to the formation of chemical bonds. calcium chloride contains bonds. a. covalent b. ionic c. metallic copper atoms are used to produce pennies. the copper atoms in pennies share many electrons. pennies contain bonds. a. covalent b. ionic c. metallic hydrochloric acid is the main acid that break down food in the stomach. the atoms of hydrochloric acid share electrons. hydrochloric acid contains bonds. a. covalent b. ionic c. metallic

An internally reversible refrigerator has a modified coefficient of performance accounting for realistic heat transfer processes of where qin is the refrigerator cooling rate, qout is the heat rejection rate, and is the power input. show that copm can be expressed in terms of the reservoir temperatures tc and th, the cold and hot thermal resistances rt,c and rt,h, and qin, as where rtot rt,c rt,h. also, show that the power input may be expressed as 1.39 a household refrigerator operates with cold- and hot-temperature reservoirs of tc 5 c and th 25 c, respectively. when new, the cold and hot side resistances are rc,n 0.05 k/w and rh,n 0.04 k/w, respectively. over time, dust accumulates on the refrigerator’s condenser coil, which is located behind the refrigerator, increasing the hot side resistance to rh,d 0.1 k/w. it is desired to have a refrigerator cooling rate of qin 750 w. using the results of problem 1.38, determine the modified coefficient of performance and the required power input w under (a) clean and (b) dusty coil conditions. internally reversible refrigerator qout qin w high-temperature reservoir low-temperature reservoir th th,i tc,i tc high-temperature side resistance low-temperature side resistance w qin th tc qinrtot tc qinrtot copm tc qinrtot th tc

Avoltaic cell converts chemical energy to

The voltage applied across a given parallel-plate capacitor is doubled. how is the energy stored in the capacitor affected?