Please help! 30 points!! You found a piece of sidewalk chalk with a mass of 15.8 grams and used it to draw on the sidewalk, so that the mass of the piece of chalk decreased to 2.1 grams. How many molecules of chalk did you leave outside on the sidewalk? (Chalk is CaCO3.)

**CaCO3 is the molecular formula for chalk. Find the Molar Mass for each part of CaCO3 and then add them together to find the total Molar Mass. This will be your conversion factor.

CaCo3 divided by the grames and subtracted by 2.1 to get your answer

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