unit 5) stochiometry Flashcards
what is a quantitive reaction
its a reaction where 99% or more complete
one reaction is completly used up (reaction wont stop till no more reactant)
whats a spontenious reaction
its a rection that occurs as soon as reactants are mixed
whats one thing that must happen to make a chemical reaction
there must be collisions collison reacttion theory- (chem entites must collide to cause a reaction)
what are the steps of net ionic equations
1- balanced chem equation
2- then they dissociate is soluble ionic compounds
3- then remove any spectator ions any that are the same on both sides
4- re-write
when do the ions in the dissociation process have coeffs
when the compound has a coeff in front or if theres a charge that was swapped onto it
when hydro carbon combustion and odd number on one side and even on other what do you do
add up coeffs that are already there then write number on the oxygen and double on the product side
what are the steps to gravimetric stoichiometry
1- write balanced chem equation / write info
2- then find moles of compound / element with the most info
3- then times required over given to find moles for thing tring to find
4- then solve for mass or whatever it is trying to find
what is the limiting regent
reactant whoes entite completly consumed in a reaction none is left over
what is execess regent
reactant entities present large amounts so some left over
whats a common way when testing stochiometry
filtering
what is the predictied value in percent yield and percent differnece
the predictied value is the stoichemestry
what is the experimental values in percent yield and percent differece
theyre info from the lab
when looking for the experimental value in percent yield what fomula do you use
exp yield= predicted times by % / 100
what are some reasons that experiments can be inaccurate
- mesuments could be rounded
- purity not always 100% pure
- washing percipitate) fine particles may be lost during filtration
-quolitative judgemnts- may think reaction do when isnt
when given an experiment and says mass of paper and mass of paper and reactant what would you first to
sub values of filter paper and compound and filterpaper combined then its just experimental and then thats the experimental value
with gas stoichemestry how do you solve
1- balanced chem reaction
2- then find number of moles if stp of satp then use n=v/vm if not use pv=nrt
3- after finding moles use reqiured/given to find moles of substance looking
4- solve for whatever value needed usally m
whats the difference between qualitative analysis and quantitative analysis
qualitative- identifying a substance present
qualntitative - identifying mass / quantitiy there
in colorimetry solution color what groups dont impact color
groups, 1, 2 and then 17
how do you identify what element goes with what color
specific elements on the table thats in the compound is the color
(look for one element on there the ion thats on the color table makes the whole compound color )
what is spectrophotometry
aq ions can be identified by eye but more precise when light produces rainbow then has sip to only show one color then detects how much absorbed
whats another way to identify elements with colors
flame colors ) several metal ions turn flames different colors
whats law conservation mass
matter cannot be made nor destroyed but the reactants just re-arrange into new products
whith quantitive analysis involving percipitation what is it combined with
its combined with excess quantity of another reactant to make sure all sample reacts
in gravimetric analysis with precipitation reaction what is it not possible to predict quantity
the quantity of excess reagent
