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Definition
| fundamentals of chemical calculations which loosely translates as "the measure of the elements." |
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Definition
| allows chemist to scale up from the atomic/molecular level to the laboratory scale. |
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Term
| What are two things you need to be successful in using analysis calculations? |
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Definition
1. acknowledge of the equalities that can be made into conversion factors.
2. a logical sequence of steps to guide us from the starting set of units to the desired units. |
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Term
| molecular mass (sometimes called molecular weight) |
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Definition
| The sum of the atomic masses (in u) of all of the atoms represented in a molecular chemical substance. |
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Definition
| the mass of one mole of a substance |
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Definition
| 6.022 x 10^23 The units of the chemicals can be atoms, molecules, formula units, and so on. |
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Term
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Definition
| Within chemical compounds, moles of atoms always combine in the same ratio as the individual atoms themselves. |
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| mass-to-mass calculations |
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Definition
| mass of A -> moles of A -> moles of B -> mass of B |
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Definition
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Definition
| the number of grams of an element combined in 100g of a compound. |
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| Percentage by mass of element= |
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Definition
| (mass of element/mass of whole sample) x 100% |
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Definition
| the formula that gives the composition of one molecule |
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Definition
| the simplest ratio of the atoms of each element in a compound |
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| Why is the law of conservation of mass and its use with percentage composition is important? |
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Definition
| it allows us to determine the amount of three substances using only two experiments |
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Term
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Definition
| a reaction in which a compound burns completely in pure oxygen |
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Term
| what are the sole products of a combustion reaction? |
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Definition
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Definition
| a method for obtaining percentage composition data for organic compounds |
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| What are the diatomic molecules? |
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Definition
Hydrogen
Nitrogen
Oxygen
Fluorine
Chlorine
Iodine
Bromine |
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Term
| What are the steps in solving a limiting reactant problem? |
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Definition
1.identify a limiting reactant problem by the fact that the amount of more than one reactant is given.
2.identify which is the limiting reactant, pick one of the reactants and calculate how much of the second reactant is needed. If the amount calculated for the second reactant is less than what is given, there is an excess of the second reactant and therefore the first reactant is limiting. If the calculated amount of the second reactant is more than what was given, then is will be consumed first and the second reactant is limiting.
3.solve the problem based on the amount of the limiting reactant at hand. For the final calculations we must use the amount of the limiting reactant given in the statement of the problem. |
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Term
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Definition
| limits the amount of product that is formed |
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Term
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Definition
| the reactant left over once the limiting reactant is used up |
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Definition
| a reaction that reduces the yield of the main product by forming by-products |
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Definition
| the substance made by a reaction that competes with the main reaction |
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Definition
| the desired reaction between the reactants as opposed to competing reactions that give by-products |
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Definition
| how much is isolated of a desired product. An experimentally determined quantity |
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Definition
| what must be obtained from a product if no losses occur. a calculated quantity based on a chemical equation and the amounts of the reactants available. |
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Definition
| the actual yield calculated as a percentage of the theoretical yield |
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Term
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Definition
| actual yield/theoretical yield x 100% |
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