genCHM1 lab final

always wear

goggles, lab coat, close-toes shoes

never pipette

by mouth

location of eyewash

location of safety shower

location of fire extinguisher

acid rule

add acid to water

accuracy

close to true value

precision

predictability

precise but not accurate

consistent but wrong

accurate but not precise

spread out but centered

average is the

sum/n

significant figures multiplication/division rule

use least sig figs

significant figures addition/subtraction rule

use least decimal places

when reading liquids

always check the meniscus

when reading the meniscus

read the bottom of curve

when reading the meniscus, read at

eye level to avoid error

density is

mass/volume

when measuring a solid through water displacement, first

measure initial water volume

when measuring a solid through water displacement, second

add object and measure new volume

when measuring a solid through water displacement, calculate

the difference between the volume of water by itself and with the solid

when measuring a solid through water displacement, the difference (calculated) is the

volume of the solid

a gas formation is a

sign of a chemical reaction (g)

a precipitate is when

a solid forms

a precipitate is a

sign of a chemical reaction (s)

color change is

a sign of chemical reaction related to physical feature

temperature change is

a sign of a chemical reaction (T)

NaCl

sodium chloride

FeCl3

iron(III) chloride

CO2

carbon dioxide

HCl

hydrochloric acid

when counting oxidation numbers, when an element is alone, the oxidation number is

0

when counting oxidation numbers, when element involved is from group 1, the oxidation number is

+1

when counting oxidation numbers, when element involved is from group 2, the oxidation number is +2

the oxidaiton number of oxygen is

-2

hydrogen has the oxidation number

+1

in measuring oxidation number of a molecule, the sum of oxidation numbers for all included elements is equal to

the molecule's overall charge

in paper chromatography, the concept is that

substances are separated based on polarity and solubility

in paper chromatography, the stationary phase is

paper

in paper chromatography, the mobile phase is

solvent

in paper chromatography, the eluent is

solvent moving up

in paper chromatography, the development chamber is the

container

in paper chromatography, the spotter is the' tool used to apply sample

Rf value=

distance spot traveled/distance solvent traveled

% of a component=(part/whole)100

hydrate general formula

salt (x H2O)

% water

(mass water/mass hydrate)100

when heating hydrate, water lost means the

mass decreases

when heating hydrate, the remainder is the

anhydrous salt

ionic compound

metal and nonmetal

naming ionic compounds step 1

name the metal

naming ionic compounds step 2

name nonmetal with -ide end

naming ionic compounds step 3

if a metal has multiple charges (normally transition), use roman numerals

(molecular compound prefixes) mono- means

1 atom

(molecular compound prefixes) di- means

2 atoms

(molecular compound prefixes) tri- means

3 atoms

(molecular compound prefixes) tetra- means

4 atoms

(molecular compound prefixes) penta- means

5 atoms

(molecular compound prefixes) hexa- means

6 atoms

(molecular compound prefixes) hepta- means

7 atoms

(molecular compound prefixes) octa- means

8 atoms

(molecular compound prefixes) nona- means

9 atoms

(molecular compound prefixes) deca- means

10 atoms

when the first element in a compound has only 1 atom, do you use mono-?

no

HNO3

nitric acid

H2SO4

sulfuric acid

stationary phase in chromatography refers to

the solid stays still

mobile phase in chromatography refers to

the liquid solvent that moves/carries substances up the paper

eluent in chromatography is the

solvent

the spotter in chromatography is

usually a capillary tube

the development chamber in chromatography

is the container where chromatography happens, holding the solvent and paper

in chromatography, separation happens because

substances interact differently with stationary and mobile phases

a hydrate is

a compound that contains H2O molecules trapped in crystal structure

in stoichiometry, to convert from g to mol, use

molar mass

the limiting reagent is the

reactant that runs out first

the limiting reagent determines

product amount

the theoretical yield is the

max product, based on the limiting reagent

percent yield=

(actual/theoretical)100

calorimetry formula

q = (m)(C)(delta T)

in the calorimetry formula, q is

heat

in the calorimetry formula, m is

mass

in the calorimetry formula, C is

specific heat

in the calorimetry formula, delta T is

change in temp

when heat is lost

is is gained by something else

metal in water

find metal's specific heat

enthalpy is

delta H

heat of reaction is

enthalpy

exothermic

releases heat

endothermic

absorbs heat

volumetric analysis is also called

titration

in volumetric analysis, analyte is

unknown

in volumetric analysis, titrant is

known

in volumetric analysis, indicator is

color changer

in volumetric analysis, equivalence point is

exact reaction

in volumetric analysis, endpoint is

indicator change

molarity is M=

moles / liters

in vinegar analysis

titrate to find concentration and calculate mass%

filtration uses

a buchner funnel and vacuum flask

in filtration, solid is separated from

liquid

in volumetric analysis, wash

solid to remove impurities

(error) overshoot titration

molarity too high