chapter 9 (thermochemistry)

Question 1

thermochemistry

Answer 1

the study of chem and energy

Question 2

energy

Answer 2

the capacity to do work or heat

Question 3

heatq

Answer 3

the flow of energy caused by a temp difference

Question 4

law of conservation of energy

Answer 4

energy can not be created or destroyed, jsut change forms

Question 5

first law of thermo

Answer 5

total energy of the universe is constant

Question 6

internal energy (state function)

Answer 6

sum of kinetic and potential energies

Question 7

state function

Answer 7

jsut depends of the current state, not how it got there

Question 8

specific heat capacity

Answer 8

the amount of energy required to raise 1 gram of X 1degree celcius

Question 9

q(amount of heat) in J=

Answer 9

mcAt

mass x specific heat x temp change

Question 10

delta E

Answer 10

E final -E intial

Question 11

Enthalpy H

Answer 11

the sum of internal energy and the product of its pressure and volume
H=E+PV

Question 12

delta H

Answer 12

deltaH=deltaE+pDeltaV

Question 13

endothermic

Answer 13

absorbs heat from the surroundings
colder
gains potential energu

Question 14

exothermic

Answer 14

gives off heat to the surrounding
hotter
releases potential energy to the masses

Question 15

does an endothermic reaction have a positive or negative H

Answer 15

positive

Question 16

does an exothermic reaction have a positive or negative H

Answer 16

negative

Question 17

quantifying delta H

Answer 17

the amount to heat absorbed or evolved in the reaction under conditions of constant pressure

Question 18

is it exothermic or endothermic

1. sweat evaporating from skin
2. water freexing in freezer
3. wood burning in fire

Answer 18

1. endothermic(cools the sin)
2. exothermic(the water releases heat and cools down(freezer removes this heat))
3. releases heat( exothermic)

Question 19

given equation,mass of one thing, heat of reaction, find heat evolved in reaction

Answer 19

find the mass in moles, then use the heat of reaction to turn it into energy with stoich

Question 20

how to find equilibrium temperature

Answer 20

use mcat and set the heat equal to eachother for both substances

Question 21

determining enthalpies from bond energies

Answer 21

^rxn = sum(bonds broken) -sum(bonds formed )

Question 22

define exothermic with bonds

Answer 22

weak bonds break and strong ones form

Question 23

define endothermic with bonds

Answer 23

strong bonds break and weak ones form