Chem 1 Lab Final (UF)

density is an _________ property of matter

intensive

% error formula

(actual - expected) / expected x 100%

measurements are said to be _______ if they yield very similar results when repeated in the same manner.

precise

a measurement is considered ________ when it yields a result very close to the true or accepted value.

accurate

NaCl solution is

non hazardous

magnesium sulfate is

non hazardous

manganese sulfate is

a health hazard, corrosive, and an environmental hazard

cupric sulfate is

an irritant and an environmental hazard

titrant

the substance being added to the analyte. The titrant is usually of known concentration.

analyte

the substance being analyzed. Often of unknown concentration.

the __ is the point at which the titrant and analyte are present in a stoichiometric equivalent ratio based on their reaction.

equivalence point

end point

where the titration ends in reality. If you are using a visual indicator, this would be where you observe the completion of the rxn.

titration curve

this can be a pH v.s. Volume curve, showing change in pH as titrant is added, for an acid/base rxn. Or it could be a graph of potential v.s. Volume of titrant added. There are other options as well...

sulfuric acid is

corrosive

ammonium cerium (IV) nitrate is

oxidizer, health hazard, irritant, and environmental hazard.

when the atmosphere exerts more pressure than the gas, use

Pgas = Patm - Pfluid

when the gas exerts more pressure than the atmosphere, use

Pgas = Patm + Pfluid

if the fluid is mercury, then

the pressure of the fluid is equal to the difference in height of the fluid level in units of millimeters

the pressure exerted by a fluid due to gravity can be calculated by the equation

P = hdg

- where P is the pressure of the fluid in units of pa

- h is the height of the fluid in meters

- d is the density of the fluid in kg/m^3

- and g is the acceleration due to gravity 9.81m/s^2

h1d1 =

h2d2

KE

3/2RT

Ptotal =

PA + PB

Ptotal

Pgas + Pvapor

units of pressure

- 1 atm = 760 mmHg

- 1 atm = 760 Torr

- 1 atm = 101325 Pa

- 1 atm = 1013 mbar

3M HCl solution

can cause severe burns and eye damage. Do not breathe, mist, or spray. May cause respiratory irritation. May be harmful if swallowed.

Mg:

flammable solid. Keep away from heat, sparks, open flames, and hot surfaces. No smoking.

both acids and bases can be corrosive (T/F)

T

halogens are unreactive (T/F)

F

mercury is readily absorbed through the skin (T/F)

F

oxidizing agents and reducing agents should be stored close to one another for safety (T/F)

F

peroxides can be stored indefinitely (T/F)

F

pyrophoric substances can burn spontaneously in air (T/F)

T

flammable liquids should be used with care near sources of ignition (T/F)

T

cryogenics are stored at high temperatures (T/F)

F

electricity can be hazardous (T/F)

T

Mg is considered flammable (T/F)

T

Mg reacts w/ water and acid solutions (T/F)

T

this concentration of HCl solution is considered flammable (T/F)

F

water can be safety added to this concentration of aqueous HCl solution.

T

this concentration of aqueous HCl is light blue in color.

F

it is safe to wash with water if one's skin is exposed to magnesium chloride solution.

T

magnesium chloride solution is considered flammable.

F

hydrogen gas is considered a carcinogen.

F

hydrogen gas is considered flammable.

T

hydrogen gas is considered an asphyxiant.

T

the last part of the lab involves...

adding a heated sample of metal to room temperature water. The temp. Change is used to determine the specific heat of the metal, and to identify the metal.

molar enthalpy of solution:

deltaH/moles

The transfer of heat resulting from an acid/base neutralization is called

enthalpy of neutralization, deltaHneutralization

qsolution=

-qrxn

Skull and Cross Bones pictogram

acute toxicity (fatal or toxic)

Person with white star on chest pictogram

Health Hazard

Exclamation mark pictogram

Irritant, Acute toxicity

Exploding pictogram

Explosive

Flame over circle pictogram

Oxidizers

Environment pictogram

Aquatic toxicity

Glass cylinder pictogram

Gases under pressure

2 test tubes being poured pictogram

Skin Corrosion and burns, eye damage

which pictogram(s) appear on the SDS for silver nitrate? select all that apply.

- irritant

- skin corrosion/burns

- oxidizer

what is the "signal word" for silver nitrate?

danger

what happens when silver nitrate is heated to composition?

may emit toxic fumes

what should be used to extinguish a fire containing silver nitrate?

water

is silver nitrate light sensitive?

yes

what color is silver nitrate?

colorless

what effect (if any) does silver nitrate have on aquatic species?

toxic

what is the melting point of 1-naphthol, according to the SDS?

96 C

is 1-naphtol air and/or light sensitive?

both air and light sensitive

what do the pictograms for 1-naphthol indicate? select all that apply.

- skin corrosion/burns

- irritant

A = Edc

- where...

- c is measured in mol L^(-1)

- d is measured in cm

- E is measured in L mol^(-1) cm^(-1)

blue 1 is

non hazardous

lambda max

is the wavelengths at which the absorbance of a given compound is greatest (characteristic of the substance)

electromagnetic radiation is aka

visible light

Particular energies are aka

wavelengths

Transmittance (T) is the fraction of light at a given wavelength that passes through a light absorbing medium. Transmittance is defined as: T = I/I0

where...

- I0 is the intensity of the incident radiation entering the medium

- I is the intensity of the transmitted radiation leaving the medium

- T is often expressed as percent transmittance, %T = 100(I/I0)

Transmittance of light through a solution decreases exponentially w/ distance or concentration. It is thus more often useful to describe the process in terms of absorbance (A), the proportion of light absorbed by the medium. Absorbance is defined as: A = log10(I0/I) = -log10T

when no light is absorbed, I =I 0 and A = 0

why should the Y-intercept of the linear trendline be very close to 0?

a y-intercept of 0 indicates 0 absorbance at 0 M concentration of colored solute.

what is the CAS registery number for sodium hypochlorite? Enter the number including dashes, for example xxx-xx-x or xx-xxx-xx, depending on how many digits are in each of the three sections.

7681-52-9

which is the best definition of asphyxiant?

can result in suffocation

which is the best definition of lachrymator?

can irritate eyes and cause tearing

which is the best definition of teratogen?

can cause birth defects

which is the best definition of mutagen?

can cause genetic mutation

which is the best definition of corrosive?

can cause damage to living tissue

describe the method of spectrophotometry

"We'll be using a spectrophotometer to monitor the absorbance of the dye sample at its lambda max."

describe how absorbance relates to concentration

the more concentrated the solute is, the more light it will absorb (A = Edc)

for zero-order rxns: [A]t = -kt + [A]0,

- mol/L v.s. Time

- slope

for first-order rxns: ln[A]t = -kt + ln[A]0,

- ln[A] v.s. Time

- slope

for second-order rxns: 1/[A]t = kt + 1/[A]0,

- L/mol v.s. Time

- + slope

describe the bleaching process in general terms

"when the dye molecule interacts w/ an oxidizing agent such as common household bleach (which contains the active ingredient NaOCl), its conjugated system is broken and the molecule can no longer absorb energy in the visible spectrum. As a result, it is decolorized."

which is the best definition of the term 'cryogenic'?

being or related to a low temp.

ionic compounds are

usually strong electrolytes and can be expected to dissociate in aqueous solution.

molecular compounds are

usually non-electrolytes. They do not form ions. Resulting solutions do not conduct electricity.

molecular acids can

partially or wholly dissociate, depending on their strength

determine which molecules or ions are responsible for conductivity of solutions

The size of the conductivity value depends on the ability of the aqueous solution to conduct electricity.

discuss how the conductivity of solutions depends on the number of ions in the compound and on the type of compound

- strong electrolytes produce large #s of ions, which results in high conductivity values

- weak electrolytes result in low conductivity

- non-electrolytes result in no conductivity

calcium chloride (CaCl2) solution is

non hazardous

Aluminum chloride (AlCl3) solution is

non hazardous

Acetic acid (HC2H3O2) solution, dilute is

non hazardous

phosphoric acid (H3PO4) solution is

harmful if swallowed; do not eat, drink or smoke when using this product. Causes severe burns and eye damage.

boric acid (H3BO3) solution is

non hazardous

HCl, dilute is

harmful if swallowed, inhaled or in contact with skin. causes skin and eye irritation.

methanol (CH3OH) solution:

may be harmful if swallowed