You have to use the sig fig rules. It depends on the number given. For example, if the number given is 1,345, the answer would be 1,350 because the 5 rounds up and the zero is not significant because there is no decimal. If the number is 0.0002056, the answer would be 2.06 x 10*-4 Refer to the online tutorial for help with the rules.
Prefixes are used for covalently bonded molecules (two non-metals). For example, if oxygen is bonded to carbon, there are several options. one carbon and one oxygen is carbon monoxide, one carbon and two oxygens is carbon dioxide. Because there are two possible combos, you have to use prefixes. In contrast, there is only one way ionic compounds (metal-nonmetal) can fit together. For example, sodium and chlorine have to go together in a 1:1 ratio so the name doesn't need prefixes.
For example, in #6 on the "Balancing Equations and Simple Stoichiometry" worksheet, you need to see how much CO2 35 grams of C6H10 would produce and then compare that to how much would be produced by 45 grams of oxygen. Then, which ever one produces less is your answer. Check out the tutorial on stoichiometry and then choose limiting reagent. Scroll half way down the page or so and check out the info under the bold heading "Limiting Reagent Problems" and look at the example problem for b)1.20 g Al and 2.40 g iodine. This will model how to do #6 on the worksheet. Let me know if you have questions on anything else.
I til don't really understand what I'm doing on the stoichiometry! I get the part of limiting reagents. Not the grams-grams problems the first ws on stoichiometry. I'm more of a visual learner.
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7 comments:
Does anyone know how to round to the 3 significant figures?
(Significant Figures Worksheet #7)
You have to use the sig fig rules. It depends on the number given. For example, if the number given is 1,345, the answer would be 1,350 because the 5 rounds up and the zero is not significant because there is no decimal. If the number is 0.0002056, the answer would be 2.06 x 10*-4 Refer to the online tutorial for help with the rules.
how do you know when to use the prefixes (mono-,di-,tri-...)?
Prefixes are used for covalently bonded molecules (two non-metals). For example, if oxygen is bonded to carbon, there are several options. one carbon and one oxygen is carbon monoxide, one carbon and two oxygens is carbon dioxide. Because there are two possible combos, you have to use prefixes. In contrast, there is only one way ionic compounds (metal-nonmetal) can fit together. For example, sodium and chlorine have to go together in a 1:1 ratio so the name doesn't need prefixes.
How do you do the stoichiometry grams-grams problems? I don't understand it.
For example, in #6 on the "Balancing Equations and Simple Stoichiometry" worksheet, you need to see how much CO2 35 grams of C6H10 would produce and then compare that to how much would be produced by 45 grams of oxygen. Then, which ever one produces less is your answer.
Check out the tutorial on stoichiometry and then choose limiting reagent. Scroll half way down the page or so and check out the info under the bold heading "Limiting Reagent Problems" and look at the example problem for b)1.20 g Al and 2.40 g iodine. This will model how to do #6 on the worksheet.
Let me know if you have questions on anything else.
I til don't really understand what I'm doing on the stoichiometry! I get the part of limiting reagents. Not the grams-grams problems the first ws on stoichiometry. I'm more of a visual learner.
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