Harry would like to investigate some basic forms of energy. He is curious about what forms of energy he uses the most on an average day. There is heat, light, electrical, chemical, and mechanical energy. What would be the best way for Harry to carry out this scientific investigation?

Sally is making a model of a magnesium atom with an atomic mass number of 24 for her chemistry class. she has foam balls for the protons, neutrons, and electrons. she has added 6 neutrons to her model so far. how many more neutrons does she need to add to complete her neutral atom of magnesium?

Based on its chemical properties, identify the position of each chemical family on the periodic table.

Which characteristics can be used to differentiate star systems? check all that apply.