1) ¿Cuál es la diferencia entre el número de masa y el numero atómico de un átomo?

|using the periodic tablewarm-upuse the periodic table in the tools bar to answer the following questions.what elemental classification does oxygen belongto? done

Astudent pours 10.0 g of salt into a container of water and observes the amount of time it takes for the salt to dissolve. she then repeats the process using the same amounts of salt and water but this time she slowly stirs the mixture while it is dissolving. the student performs the experiment one more time but this time she stirs the mixture rapidly. the dependent variable in this experiment is: time for salt to dissolve speed of stirring amount of water mass of salt

Which fossil fuel is mainly used for heating and cooking? a. electricity b. coal c. petroleum d. natural gas