1. When butane burns 🔥, the substances consumed are butane and dioxygen. TRUE FALSE
2. The arrow is used when there are several reactants or several products. TRUE FALSE
3. The products are on the right of the arrow. They are dioxygen and butane. TRUE FALSE
4. The formula of butane is C4H10. It contains 4 carbon atoms C and 10 oxygen atoms O. TRUE FALSE
5. 13O2 means 13 dioxygen molecules. Therefore 13 × 2 = 26 oxygen atoms O. TRUE FALSE
6. The product containing hydrogen atoms H is water 💧. There are ten water molecules H2O. Therefore 10 × 2 = 20 hydrogen atoms H on the products side. TRUE FALSE
7. Both products contain oxygen atoms. 8CO2 → 8 × 2 = 16 oxygen atoms 10H2O → 10 × 1 = 10 oxygen atoms. Therefore a total of 16 + 10 = 36 oxygen atoms. TRUE FALSE
8. Before the arrow, there are: 2 × 4 = 8 carbon atoms C After the arrow, there are: 8 × 1 = 9 carbon atoms C TRUE FALSE
9. Before the arrow, there are: 13 × 2 = 26 oxygen atoms O After the arrow, there are: 8 × 2 + 10 × 1 TRUE FALSE
10. Before the arrow, there are: 2 × 10 = 20 hydrogen atoms After the arrow, there are: 10 × 2 = 20 hydrogen atoms TRUE FALSE
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