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Balance this equation co2(g) + h2o (g) show that the balanced equation obeys the law if conversation of mass

Several kinds of bears are found on earth. most bears are brown or black, but one type of bear, the polar bear, is white. what process led to this difference in fur color? explain your answer.

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?