Chemistry equations

Question 1

Formula used to find fingerprint of gaseous elements

Answer 1

f= frequency lambda=wavelength c= speed of light h= plank’s constant (6.63 x 10^-34 J•s)

**Can only predict E of atoms or ions with one electron (Bohr atom)

Change in E predicts wavelength of photons emitted when electron fall to lower E level (emission) or jump to higher E level (absorption)

Question 2

Name the type of radioactive decaythat can be stopped by skin or paper

Answer 2

Alpha Decay

Question 3

Type of radioactive decay that emits 2 protons and 2 neutrons

Answer 3

Alpha Decay

Question 4

210₈₄PO ►206₈₂PO

Answer 4

Alpha Decay

Question 5

Too many neutrons, so neutron is converted to proton + electron

Answer 5

Beta Neg. decay

Question 6

Atomic Number + 1

Answer 6

Beta Neg Decay

Question 7

14₆C►14₇C

Answer 7

Beta Neg Decay

Question 8

Too few neutrons, proton ocnverted to neutron and poistron

Answer 8

Beta Pos. Decay

Question 9

Atomic # = -1

Answer 9

Beta Pos. Decay or Electron Capture

Question 10

18₉C►18₈C

Answer 10

Beta Pos Decay

Question 12

What is the difference b/w Electron Capture and Beta Pos. Decay?

Answer 12

both have too few neutrons, but electron capture captures electron from closest shell to convert proton into neutron. Beta pos. decay converts proton into neutron without capturing electron.

Question 13

What type of radioactive decay needs concrete or Lead to stop?

Answer 13

Gamma Decay

Question 14

Atomic # and mass stay the same in what radioactive decay?

Answer 14

Gamma

Question 15

What does Gamma Decay emmit?

Answer 15

gamma photons

Question 16

Nuclear Binding Energy

Answer 16

c=3x10⁸m/s

1ev= 1.6x10^-19J

1amu= 1.66x10^-27kg

E_Bin ev for equation

m in amu

Question 17

The greater the binding energy, the more ______ the nucleus

Answer 17

stable

Question 18

Formal Charge Equation

Answer 18

FC=V-1/2B-L

FC= formal charge

V=#valence electrons

B=#bonding electrons

L=#lone-paired electrons

Question 19

Amount of E required to complete transition ___

Answer 19

heat of transition (Delta H)

Question 20

what is formula for calculating energy required to complete phase transition/change

Answer 20

q=nXΔH

q=heat

n= #of moles

H=change of phase change

Question 21

q=nXΔH

q and H are +, heat is _____

Answer 21

absorbed

Question 22

q=nXΔH

q and H are -, heat is _______________

Answer 22

released

Question 23

To calculate temperature change in a reaction

Answer 23

q=mcΔT

q=heat added or released

m=mass of sample

c=specific heat of substance

Question 24

What is specific heat?

Answer 24

How resistant a substance is to change in temperature. The greater the specific heat, the less there will be a change in temperature

Question 25

Define calorie

Answer 25

Amount of heat required to raise 1 gram of water by 1degree C

Question 26

1cal= ?J

Answer 26

4.2

Question 27

1atm=?torr=?mmHg (pressure)

Answer 27

760, 760

Question 28

1cm³=?cc=?mL | (volume)

Answer 28

1cc, 1mL

Question 29

1m³=?L | (volume)

Answer 29

1000

Question 30

1atm=?kPa=?Pa | (P)

Answer 30

101.3kPa 1x10⁵Pa

Question 31

The ideal gas law

Answer 31

PV=nRT R=universal gas constant (.0821L-atm/kmol) T in kelvins

Question 32

combined gas law

Answer 32

P₁V₁/T₁=P₂V₂/T₂

Question 33

At constant P, how does V relate to T?

Answer 33

V₁/T₁=V₂/T₂

Question 34

At constant T, how does P relate to V?

Answer 34

P₁V₁=P₂V₂

Question 35

At constant V, how does P relate to T?

Answer 35

P₁/T₁=P₂/T₂

Question 36

Boiling Point elevation equation?

Answer 36

ΔT_b=k_bim k_b= solven's boilng point elevation constant i is van't hoff factor (basically how many ions are in it?) m= molal concentration of the solution (molal=#mol/kg)

Question 37

Freezing point depression equation?

Answer 37

ΔT_f=k_fim

Question 38

van't hoff equation? aka osmotic P

Answer 38

Π=MiRT Π=osmotic P in atm M-molarity i=van't hoff factor (how many ions?) R=Planks constnat .0821 L•atm/k•mole T = T in K

Question 39

If keq \< 1 → If keq = 1 → If keq \> 1 →

Answer 39

rxn favor reactants rxn balances reactants and products rxn favors products

Question 40

keq stands for, which is constant IF \_\_\_\_\_\_\_\_\_\_\_

Answer 40

equilibrium constant, constant if T is constant

Question 41

Q stands for \_\_\_\_ if Q \< Keq \_\_\_\_\_\_ if Q \> Keq \_\_\_\_\_\_\_\_\_

Answer 41

reaction quotient when rxn is not at equilibrium Rxn proceeds forward Rxn proceeds backwards

Question 42

k_sp stands for

Answer 42

solubility product constant - how easily a salt dissolves in water

Question 43

In a problem with solubility constant (ksp) what is left out of equation?

Answer 43

solids

Question 45

What does Ka stand for?

Answer 45

acid ionization - tells if products or reactants are favored.

Question 46

The larger the Ka value the _____________ the acid

Answer 46

stronger (Ka\>1 is a strong acid)

Question 47

What does k_w stand for?

Answer 47

autoionization of water aka the ion product constant of water

Question 48

What is the k_w of water at 25ºc?

Answer 48

1 x 10^-14

Question 49

What is the formula for PH in its relation to acids? Bases?

Answer 49

PH = -log [H⁺] [H+]=10^-PH pOH=-log[OH^-] [OH-]=10^-pOH

Question 50

What is the neutralization formula?

Answer 50

a x [A] x V_A= b x [B] x V_B a = # of acidic hydrogens per formula unit, b = how many H⁺ ions the base can accept V_A is volume of acid, same for Vb, A is concentration of acid

Question 51

Henderson-Hasselbach equation

Answer 51

pH=pka + log( [CB]/ [weak acid] )

Question 52

First law of thermodynamics equation

Answer 52

ΔE=q+w Change in E = heat + work

Question 53

Gibb's free energy equation

Answer 53

ΔG = ΔH - TΔS H - enthalpy S - entropy

Question 54

What does ΔG tell you about chemical rxn?

Answer 54

Whether it's spontaneous or not.

Question 55

If... ## Footnote ΔG \< 0 ΔG = 0 ΔG \> 0

Answer 55

spontaneous, forward directoin equilibrium nonspontaneous

Question 56

What is the equation for Gibbs free Energy at equilibrium?

Answer 56

ΔG^º = -RT lnK_eq

Question 57

What equation relates Gibbs free energy to redox rxns?

Answer 57

ΔG^º = -nFEº n = # of moles of E transferred F is constant = 96500 coulombs Eº = reduction potential

Question 58

At STP 1 mole of an ideal gas occupies ?L

Answer 58

22.4L