This is the Snapquiz on Empirical Formula. Click here or use the embedded video if you haven't watched the lesson yet.

Question 1. How would you find the mass increase due to oxygen in the oxidation of magnesium? Subtract the mass before oxidation from the mass after oxidation. Find the ratios of the masses before and after oxidation. Subtract the mass after oxidation from the mass before oxidation. Add the masses before and after oxidation together.

Question 2. A carbon oxide is found to have a 1:1 ratio of carbon to oxygen. What is its correctly-written empirical formula? CO_{2} C_{1}O_{1} CO C_{2}O

Question 3. What's the next step once you've found the mass in grams of an element in your compound and its A_{r} value? Subtract the A_{r} value from the mass. Divide the mass by the A_{r} value. Find the ratio of the A_{r} values to each other. Find the ratio of the mass to the A_{r}

Question 4. Butene contains four carbon atoms and eight hydrogen atoms. What is its empirical formula (not its molecular formula)? C_{4}H_{8} CH CH_{2} C_{2}H_{4}

Question 5. 89.2g of lead oxide is heated with carbon, which reduces it (removes its oxygen). Afterwards 82.8g of pure lead is left. How would we find the mass of oxygen lost? Divide both values by A_{r} values. 89.2g - 82.8g 82.8g - 89.2g Simplify the ratio 89.2 : 82.8

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