Acovalent bond between two atoms occurs when the atoms a. lose or gain electrons and become ions. b. share pairs of electrons. c. transfer valence electrons completely from one atom to another. d. have an electrical attraction between them.

If e is the symbol for an element, which two of the following symbols represent isotopes of the same element? 1. e2. e3. ea.1 and 2c.1 and 4b.3 and 4d.2 and 3

Which of these describes how heat is transferred by convection* a. sunlight travels through space without the aid of fluids or solids. b. warm air rises and takes the heat with it, eventually, it cools and sinks c. air at the equator rises and sinks at the poles. d. air molecules touch the warm ground, heating them up *not conduction

If you try to move a piano and are unable to move it, did you perform any work in the scientific sense of the word? yes or no?