Final Study for Chemistry

All of moduals from6-8

How does energy play a role in bonds

Energy is required for breaking bonds and released when forming bonds

How can energy be released

Heat, sound, light

Molarity equation

( mols of solute over L solution)

Dilution equation

C1V1=C2V2

What does an ideal gas consist of

1. Particles have no volume

2. Particles exert no pressure on each other 

3. Particles are in constant motion

What is the STP of a gas

1atm, 22.4 L and 273.15K

What does pressure equal

The force/ area

The ideal gas law eqauation

PV=nRT

Combine gas law

Scub diving sceneries (P₁V₁/T1 = P₂V₂/T₂)

When do we use the combined gas law

when the number of moles is kept constant under two different conditions. 

What is avagodro’s revised law

Volume of a gas is directly proportional to the number of moles. (Only if the volume is measured at the same temp and pressure)

Molar mass equation

Mass of substance divided by the moles (m/n)

PV=nRT converted to molar mass

Molar mass= mRT/PV

Density equation

PM/RT

Explain partial pressure

is the pressure exerted by each individual gas in a mixture

Explain Mole fraction

Unit of concentration of a pressure

What does the total pressure equal 

The total pressure of a mixture equals the sum of all partial pressures 

Mole fraction equation

Number of moles(n)/Total number of moles(Ntotal) 

Partial pressure equation

Partial pressure= Mole fraction times Total pressure

Combining of chambers equation

P1V1=P2V2

What role does temperature play on a gas

The temperature gives us the Avg KE of a gas

What does KE equal

3/2RT and 1/2mv² for a single particle

What does Vrms mean

is a measure of the speed of gas molecules

Vrms eqaution

Square root( 3RT/M) Molar mass most be in Kg

Diffusion rate equation

Square root ( M_b/M_a) (constant temp and pressure)

Thermochemistry definition

amount of heat released/absorbed during a chemical reaction

Potential Energy

energy that is dependent on the position, composition, condition of an object.

Kinetic energy

Energy a object has based on its motion

How is chemical energy stored

its stored in the bonds of molecules

What is difference between exo and endo in phase changes

(Solid—>Liquid—>Gas) and breaking chemical bonds Endothermic 

(Gas—→liquid—→solid) and Forming chemical bonds Exothermic

What does the physical and chemical exo/endo graphs look like.

draw them

Relationship between KE and Potential energy

as one decreases, the energy of the other must increase

Enthalpy (H) and exo/endo

a measure of the total heat content of a system. Positive-Endothermic, Negative-exothermic

How do particles move with Kinetic energy between phase changes.

Solid- Rotation, Vibration Liquid/Gas- Vibration, rotation, translation

What is thermal energy and is it extensive/intensive

this is the kinetic energy associated with the random motion of molecules. Extensive

If we increase the thermal energy what are the affects

Average KE and temperature increase

How does thermal energy play a role in two different temperature substances 

The two substances will reach a equilibrium of temperature and have the same thermal energy. 

Heat flow

Heat flow is the amount of heat flowing between two substances and they meet at equilibrium

What role does energy flow play in Exo/Endo and system vs surrounding

Exothermic reactions will have energy flowing from the system to the surroundings, and endo will have heat flowing from the surrounding to the system with POV system. 

q_system=-q_surondings

This equation means that since no energy can be created nor destroyed the energy leaving or entering a system must be equal and balance with the surroundings. 

Internal energy (E or U)

The total energy in a molecule

Work (w)

is the process of moving matter a distance

Relationship between E and KE/Potential energy

as KE or potential energy increases E increases.

How is energy that is transferred from the surroundings to the system characterized

We use heat(q) and Work(w)

How is energy transferred between two substances

through collisions between the molecules.

what does work equal

-P(change in volume)

Explain the selfish rule

ME(system) if im absorbing heats (+) and if work is done on me (+) if heat is leaving me (-) and I am doing the work (-)

Internal energy equation

q+w

what is a constant volume system, and what does the q_v=

a volume or container were the volume of the gas above a liquid can’t change, q_v=(change in E)

What is a constant pressure system and what does q_v=

a container where the volume of the gas can change, to maintain constant pressure q_v=  (change in energy) + P(change in volume)

Heat capacity (C)

Represents the quantity of heat required to raise the temperature by 1 degree

Is heat capacity extensive or intensive

extensive, more of the substance more ways to store energy

Specific heat ©

is the required heat to raise 1g of a substance 1 degree (intensive)

heat capacity equation

q/(change in temp)

specific heat capacity

q/m(change in temp)

how can we solve the amount of heat entering or leaving a substance

q=cxmx(change in temp)

Exothermic reaction in a calorimetry vs endo

exothermic reactions produce heat that is absorbed by the solution, endothermic takes heat from the solution and decreases the temperature. 

Change in enthalpy _fus and endo/exo when

is the energy exchange between changing phases, endo=(+) exo(-)

why is the entholpy of (s) to (l) 6.0KJ/Mol and (l) to (g) 44.01

solid to liquid, the hydrogen bonds are only partially disrupted. However, for the phase change from liquid to gas, the hydrogen bonds must be completely broken as the water vapor molecules ideally do not interact at all

heat flow equation for a phase change

q= m ±(H_fus)

when do we use Hess law, and when do we use the standard equation

when given Δ_fH° use eequation if u only have ΔH° hess law

equation for standard

n x (Δ_fH°(products) - n x Δ_fH°(reactants)

photoelectric effect

occurs when light of a high frequency strikes metal and ejects electrons. 

Equation for the energy of a photon

E=hv, c=v(wavenlength) E=hc/(wavenlength)

what are the constants

h= 6.626 × 10^-34 J·s, c= 2.998 × 10⁸ m/s, m=9.11 × 10^-31 kg

equation for speed, and wavelength and frequency

c=(wavelength)(Frequency)