Which is a substance that cannot be broken down into another substance? compound
element
atom
molecule

An atom with 7 protons, 6 neutrons, and 7 electrons has an atomic mass of amu. (enter a whole number.) numerical answers expected! answer for blank 1:

What is a difference between a mixture of elements and a mixture of compounds

Which of the following is an example of how telecommunication devices people do their jobs? a.) a security guard checks the time using a digital watch. b.) a banker does some quick math using a solar calculator. c.) a nurse uses a digital thermometer to take a patient’s temperature. d.) a construction worker reports in to his office using a cell phone.