What type of reaction is 4 Fe +3 02 → 2 Fe2O3

You are making a solution of calcium chloride dissolved in water. you add solid, stir, and it dissolves. you add just a spatula tip full, stir, and the solid does not dissolve. how could you describe the solutions before and after adding the spatula tip amount

How have the greenhouse gasses increased from the year 2000 to 2018

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