Chaptet 5 Thermochemistry

Question 1

Work formula

Answer 1

Force x Distance

Question 2

Kinetic energy formula

Answer 2

KE = 1/2mv^2

Question 3

Force necessary to lift weight formula

Answer 3

= m x g
G = gravitational constant = 9.8 m/s^2

Question 4

Work due to expansion =

Answer 4

W= -P🔺V

Question 5

Open system

Answer 5

Both matter and energy can cross boundary

Question 6

Closed system

Answer 6

Heat can flow in or out, matter cannot

Question 7

Isolated system

Answer 7

Neither heat or matter can flow in or out of

Question 8

🔺E is

Answer 8

Change in internal energy

Question 9

1st law of thermodynamics is (in words)

Answer 9

Change in internal energy of system = (heat “q” added or released from system) + (work “w” done on or by the system)

Question 10

1st law of thermodynamics equation

Answer 10

🔺E= q+w

Question 11

If heat comes from surroundings and goes into system, “q” is

Answer 11

Positive

Question 12

If heat comes from system and goes to surroundings , “q “ is

Answer 12

Negative

Question 13

If work if done by surroundings and done on the system, “w” is

Answer 13

Positive

Question 14

If work done by system and done on surroundings “w” is

Answer 14

Negative

Question 15

H =

Answer 15

Enthalpy

Question 16

Enthalpy equation

Answer 16

H = E + PV

Question 17

🔺H is the

Answer 17

Change in enthalpy

Heat “q” added or released by system at constant pressure

Question 18

🔺H (reaction) is

Answer 18

Heat given off or absorbed during the course of reaction

Question 19

🔺H(temp bubble) (reaction) is

Answer 19

Heat of reaction that occurs under standard conditions

Question 20

Standard conditions

Answer 20

1 atm pressure, 238 K

Question 21

🔺H (f) means

Answer 21

Heat of reaction that produces one mole of a product from elements

Question 22

🔺H (bubble) (f) means

Answer 22

Heat of reaction that produces one mole of product from elements under standard conditions

Question 23

Reaction that releases heat…(4)

Answer 23

• 🔺H is negative
• exothermic
• heat is product
• Reactants have higher enthalpy

Question 24

Reaction that absorbs heat…(4)

Answer 24

• 🔺H is positive
• Endothermic
• Heat is reactant
• Products have higher enthalpy

Question 25

How much heat must be added to cause certain temperature change formula :

Answer 25

Heat (q) = mc🔺t =(mass)(specific heat)(🔺temp)

Question 26

Formula for how much heat is needed to melt things

Answer 26

Heat = (mass) x (heat of phase change) Constant = 79.6 cal/g (one gram of ice)

Question 27

Creating a gas _____ the volume

Answer 27

Increased

Question 28

The system is the _____

Answer 28

Reaction