Flashcards
Moles
Flashcards do conjunto (13)
- 1Define Relative atomic massThe mean relative mass of all the isotopes of an element, compared with the standard carbon atom.
- 2define relative formula massall of the masses of each element in a compound, added up
- 3Define molea mole of a substance is simply the RFM or RAM of it expressed in grams. A mole of a substance always has the same number of ions, molecules, or atoms in a mole: 6.02x10^23.
- 4define Avagadro's constant6.02x10^23
- 5Give the formula connecting moles, mass, and and Ar or MrMoles = Mass/Mr
- 6What can you tell from a balanced symbol equationYou can tell how many moles of each substance, and what mass of a substance, you need to carry out the equation
- 7Give the steps to balancing equations using moles1) find the masses of each substance
2) Find out how many moles of each substance you have
3) find the whole number ratio of numbers of moles - 8Define limiting reactantThe reactant that gets used up first in a reaction
- 9Give the formula for percentage yield.yield:
actual mass produced/maximum theoretical mass of product possible - 10Give factors why yield may not be 100%1) the reaction is reversible
2) some reactants produce unexpected products
3) some product left behind in the apparatus
4) reactants may not be completely pure
5) may be difficult to separate product we want - 11What is atom economythe measure of the extent to which the atoms in the starting materials ends up in the desired product
- 12why is atom economy important?It saves money, and wastes less raw materials; it also reduces pollution and the number of limited resources used.
- 13what is the equation for atom economyrelative formula mass of the desired product
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sum of RFM of reactants of the equation