ch. 4 learnsmart part 1

What information can be gained from a balanced chemical equation?

* The relative quantities (moles) of substances involved * The identities of substances involved * The physical states of reactants and products, often, but not always included.

to present a chemical change quantitatively, an equation must be balanced meaning....

...meaning the same number of each type of atom must appear on both sides.

in a balanced equation, the amounts (mol) of substances are stoichiometrically equivalent to each other which means...

...which means that a specific amount of one substance is formed from, produces, or reacts with a specific amount of the other.

3 step process to find the overall percent yield

1. express the yield of each step as a decimal 2. multiply all the decimal amounts together 3. convert back to a percentage OR!! simply multiply the individual % yields by each other.

What, in order, are the steps necessary to solve for the mass of a product, or second reactant required, given the mass of one of the reactants in a chemical equation?

1. write a balanced equation for the reaction 2. convert the given mass into moles using molar mass. convert moles of A to moles of B using a conversion factor derived from the balanced equation. 3. convert the moles of the second substance to mass using its molar mass.

Chemical equation

a statement that uses formulas to express the identities and quantities of substances involved in a chemical or physical change.

Isomers

compounds with the same molecular formula, and thus molar mass, but different properties.

the compounds depicted are ________ isomers because they have the same _______ formula but have different _________ formulas.

constitutional, molecular, structural

percent yield

is the actual yield expressed as a percentage of the theoretical yield

which of the following actions are permitted in balancing a chemical equation?

multiplying al coefficients by a common factor & inserting coefficients in front of formulas of reactants and products.

A chemical equation must be balanced. This means that the same _____ and ________ of atoms must appear on both sides of the equation.

number; type

True or false: the percent yield (% yield) is ALWAYS less than 100%.

true

How do constitutional or structural isomers occur?

when the atoms link together in different arrangements.