Microave energy transformation

Which class of molecules functions as chemical signals? hormones water carbohydrates proteins

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

How many grams of mgbr2 are needed to produce 75g or metal?