Crude copper has many metal impurities (for example, lead, zinc, nickel, and others) and does not conduct electricity well, so ultrapure copper is needed. Explain how an electrochemical cell is used to purify copper. You may include a diagram of the electrochemical cell in your explanation.

What rule is used to determine how many covalent bonds an element can form? a. the number of covalent bonds is equal to six c the number of covalent bonds is equal to five minus the group number plus the group number b. the number of covalent bonds is equal to eight d. none of the above minus the group number select the best answer from the choices provided