Chem Exam 3

when looking for wavelength and given a value in m/s which equation would you use?

λ = h/ mv

where λ is the wavelength, h is Planck's constant, m is the mass, and v is the velocity of the particle.

when given pressure and two volumes, what are you looking for and which equation finds it

w = -PΔV

what is the standard equation for Energy

E = q + w

what is the equation for finding energy in a bomb calirimeter

E = C_cal ΔT

when working with a sample that is burned in a bomb calorimeter, is the heat capacity positive or negative

negative due to the system losing heat.

when solving for T_f of two substances, what should you add to the equation of one side

a negative

-q_surr = +q_sys

when looking for the Energy of a reaction in a cup calorimeter, which equation should you use

E = mCΔT

when seeing the words “calculate the heat associated” and given mass with a balanced equation and ΔH of the reaction, what should you expect to do

use the mass and cancel out until you find the KJ

When given ΔHf and looking for ΔHrxn, which equation should you use

ΔH = ΔHproducts - ΔHreactants

radius size increases going what way

moving down a group and to the left across a period.

a larger Zeff means a smaller or larger radius?

a smaller atomic

a smaller Zeff means a smaller or larger radius?

larger

first IE (ionization energy) increases going what way on the periodic table

moving up a group and to the right across a period.

when a system produces heat and does work do we assume the sign of the systems energy to be, the surroundings energy to be, and what can we assume the signs of w and q to be?

the system will ne negative

the surrounding will be positive

-w and -q

if heat is absorbed what can we expect the sign of q to be

positive and indicates endothermic process

what is the conversion factor of Jules to Latm

101.3 J = 1 Latm

when given a mass in a bomb calorimeter equation, what can you expect to use the mass for?

go from grams → moles and dived q (kJ) by the moles to get ΔE (kJ/mol)

when given a mass of an element and a mL of a solution, which do you plug into the q = mCsΔT and which do you use molar mass to convert to moles to divide q by to find ΔHrxn (kJ/mol but leave out the mole i think)

You plug the mL of the solution into the q = mCsΔT equation and use the mass of the element with its molar mass to convert to moles for calculating ΔHrxn.

shorter wavelength means what frequency

higher (greater) frequency

what is the relationship between radiation and energy

Higher energy corresponds to shorter wavelength.

If youre given wavelength and u need energy which equation do you use

E = hc / λ

greater velocity means what wavelength

shorter wavelength

the distance between adjacent crests is called

wavelength

the height of a wave from the center line to a crest is called

amplitude

if two e^- in the same atom have the same value of l, they are

in the same sublevel but not necessarily the same level

how many orbitals in n = 3

9

how many subshells in n = 6

6

how many subshells in n = 4

4

when dealing with electrons going to different levels, which equation do we use

ΔH = -2.18E-18 (1/nf² - 1/ni²

a type of energy embodied in oscillating electric and magnetic fields is called

electromagnetic radiation.

in the c = vλ c = what

3.00E8 m/s

in E = hv, h = what

6.626E-34 J·s

which quantum number describes the size and energy of an orbital

principal quantum number

(n) in quantum mechanics.

which quantum number describes the shape of an orbital

angular momentum quantum number (l)

which quantum number describes the orientation of the spin of the e^-

spin quantum number (s)

when in the s orbital l = what

0

no 2 e^- in an atim can have the same four quantum numbers is known as

the Pauli exclusion principle.

the pattern for filling up the e^- configuration, from low to high energy for an element is called the

Aufbau principle.

paramagnetic

unpaired electrons, magnetic

diamagnetic

paired electrons, no magnetism

how many VE in alkaline earth metals

2

define work

the result of force acting through a distance

define energy

the capacity to do work

what are two ways an object can exchange energy with another object

Through work or heat transfer.