Please help

How do you know how many
electrons an atom has?

The number of neutrons is equal to the atomic number minus the atomic mass. a. true b. false

Which of the following best describes technology a. something created for only scientists to use b.the method of thinking that scientists use. c.the application of engineering to create useful products. c. a scientific idea

La reaccion entre monoxido de nitrogeno (no) y oxigeno para formardioxido de nitrogeno (no2) es un paso determinante para la formacion del smog, la reaccion es la siguiente: 2no + o2 = 2no2 cual sera el numero de moles de no2 que se formaran por la reaccion completa de 8 moles de oxigeno con suficiente monoxido?