Which of the following chemical formulas shows a covalent compound? a. co2 b. mgo c. nacl d. hbr

Acontrol during an experiment. might change remains constant does not exist does change

13. a covalent bond between two atoms is likely to be polar if: a. one of the atoms is much more electronegative than the other. b. the two atoms are equally electronegative. c. the two atoms are of the same element. d. the bond is part of a tetrahedrally shaped molecule. e. one atom is an anion.

In an exothermic reaction, energy may be released to the surroundings in the form of question 4 options: heat light thermal all of the above