Write a balanced chemical equation for calcium carbonate and water

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?

How does a coronal mass ejection (cme) affect the solar wind? a cme adds more particles to the solar wind, intensifying it. a cme blocks the solar wind, causing it to fade. a cme does not affect the solar wind but it does affect auroras. a cme increases the amount of energy in the solar wind.

How does science use models to gain a better understanding of concepts?