why do the elements in the tube have to have high voltage electricity run through them before the colored light is emitted

In which situation can a mixture always be called a solution

Scientific evidence tells us that the cause of earths four season is the tilt of earth as it revolves around the sun. the student is instructed to illustrate this information in a science notebook. how will the student illiterate winter in the northern hemisphere?

Which of the following changes will decrease the total amount of gaseous solute able to be dissolved in a liter of liquid water? (2 points) decreasing temperature decreasing pressure decreasing surface area decreasing solute concentration