Chem 110 Final

Question 1

How to calculate the atomic mass?

Answer 1

Sum of (Isotopic mass times relative abundance of isotope) for each isotope

Question 2

If energy is gained by the system and lost by the surroundings is the change in energy positive or negative?

Answer 2

Positive

Question 3

If energy is lost by the system and gained by the surroudings is the change in energy positive or negative?

Answer 3

Negative

Question 4

How to calculate formal charge?

Answer 4

Valence e - Lone e - Bonds

Question 5

What is fusion?

Answer 5

Solid to liquid, which is positive

Question 6

What is sublimation?

Answer 6

Solid to gas which is positive

Question 7

Condensation?

Answer 7

Gas to liquid, negative VAP

Question 8

Freezing?

Answer 8

Liquid to solid, Negative FUS

Question 9

Deposition

Answer 9

Gas to solid, Negative SUB

Question 10

Strong Acids are:

Answer 10

Hydrohalic acids starting with Cl and going down. (HCl, HBr)

Oxoacids where there are at least two more O atoms than there are ionizable H atoms (HNO3, HClO4)

Question 11

Weak acids are:

Answer 11

Acids where H is not bonded to an O or a halide (HCN)

Ocoacids where there are less than two more O atoms than there are ionizable H atoms (HNO2 and HClO)

Organic Acids, (R-COOH)

Question 12

Strong Bases

Answer 12

M2O and MOH, where M is any group 1 metal

M(OH)2 and MO where M is Ca, Sr or Ba

Question 13

Weak Bases

Answer 13

Any compound with a lone electron pair on an N atom (NH3)

Question 14

Using the Heats of Fortmation to determine Heats of Reaction?

Answer 14

Sum of moles of heat of formation of PRODUCTS minus sum of moles of heat of formation of REACTANTS

Question 15

Using Bond Dissociation Energy to Calculate Heats of Reaction

Answer 15

Reactants minus Products

Question 16

Using Stoichiometry to calc. Heats of Reaction

Answer 16

You may need to find the limiting reagent and find the lowest number moles.

Question 17

Using Hess’s Law to calculate Heat of Reaction.

Answer 17

A + B = C, AH1
B+D=A+C, AH2
_______________
A+2B+D=A+2C

Cancel common facotrs.

Question 18

Eq. Constants based on Pressure

Answer 18

A+B=C

Kp = (Pc)/ Pa * Pb

Question 19

What happens if you increase the PRODUCTS?

Answer 19

The reactions proceeds RIGHT-LEFT, and more the REACTANTS INCREASE, and PRODUCT DECREASE

Question 20

What happens if you DECREASE the REACTANTS?

Answer 20

The reaction proceeds right RIGHT-LEFT and more REACTANTS INCREASE AND PRODUCTS DECREASE

Question 21

What happens when the pressure of PRODUCTS is incrreased?

Answer 21

SHIFTS REACTION RIGHT TO LEFT

Question 22

What happens when the pressure of the reactants increasE?

Answer 22

SHIFTS REACTION LEFT TO RIGHT

Question 23

If the total pressure increases?

Answer 23

The reaction proceeds in the direction with less moles of gas

Question 24

If the total pressure decreases?

Answer 24

The reaction proceeds in the direction with more moles of gas

Question 25

Changing tempreture for Endothermic reactions (Positive)

Answer 25

Increasing shifts left to right

Question 26

Changing temp. for Exothermic reactions (Negative)

Answer 26

Increasing shifts right to left