Chapter 10 energy chapter 11 Electron Configurations

Question 1

energy

Answer 1

the ability to do work or produce heat

Question 2

potential energy

Answer 2

energy due to position

Question 3

kinetic energy

Answer 3

energy due to movement

Question 4

law of conservation

Answer 4

states that energy can be converted from form to another but can be neither created or destroyed.

Question 5

temperature

Answer 5

is a measure of the random motions of the components of a substance. It is the average kinetic energy of a substance’s particles.
Temperature is measure in c or K.

Question 6

Heat

Answer 6

is the energy transfer from one object to another. Energy is transferred from the hotter object to the colder object. heat is measured in calories or joules.

Question 7

Endothermic reactions

Answer 7

absorb heat from the surrounding. Heat of the reaction is positive (+). example: heat liquid water to boiling

Question 8

exothermic reactions

Answer 8

release heat to the surrounding. Heat of the reaction is negative (-). Example: lighting a match.

Question 9

calorie

Answer 9

is the amount of energy (heat) required to raise the temperature of 1 gram of water by 1 celsius degree.

Question 10

1 calorie

Answer 10

1 calorie =4.184 Joules

Question 11

Specific heat

Answer 11

is the amount of energy required to change the temperature of one gram of a substance by one celsius degree.

Question 12

specific heat capacity

Answer 12

is used to calculate the heat required to increase the temperature of a given amount of a substance.

Question 13

specific heat formula

Answer 13

Q= m x s x ^T
q= heat required (can be positive or negative
m= mass of substance
s= specific heat of substance
^T= change in temp ( final temp- initial temp)

Question 14

Periods or rows

Answer 14

in the periodic table represent the energy levels possible for electrons. you find 2 elements in period 1 so that the 1st principle energy level can hold 2 electrons. 8 elements are found in period 2, therefore the 2nd principle energy level hold 8 electrons.

Question 15

2 elements in period one so the 1st principle energy level

Answer 15

can hold 2 electrons

Question 16

8 elements are found in period 2

Answer 16

therefore the 2nd principle energy level holds 8 electrons

Question 17

Bohr Model of the Atom

Answer 17

• nucleus contains the protons and neutrons

- electrons are found outside of the nucleus in circular orbits at varying energy levels,

Question 18

Wave Mechanical Model

Answer 18

• using this model electrons are found in orbitals not orbits.
• an orbital is a regions where an electron can most probably be found.
• they move in all directions, not just a circular orbit.
• each orbital can hold 2 electrons.

Question 19

each energy level can be broken down

Answer 19

into sublevels

Question 20

4 types of sublevels

Answer 20

s: 1 orbital - contains 2 electrons
p: 3 orbitals - contains 6 electrons
d: 5 orbitals - contains 10 electrons
f: 7 orbitals - contain 14 electrons (these we are not going to look at)

Question 21

Electron configuration

Answer 21

You can write electron configurations for any elemet using the energy level sublevels and number of electrons found in each sublevel.

Question 22

Valence electrons

Answer 22

the electrons found in the outer most energy level.
the number of valence electrons determines the chemical properties of the element.
-the noble gases in group 18 are non-reactive because they have a full outer energy level (octet).
-all of the other groups of elements want to have an octet, so they gain, lose or share electrons with other elements.

Question 23

the number of valence electrons determine

Answer 23

the chemical properties of the elements.

Question 24

noble gases in group 18

Answer 24

are not reactive because they have a full energy level.(octet)

Question 25

all other groups of elements

Answer 25

want to have an octet, so they gain,, lose, or share electrons with other elements.

Question 26

ionization energy

Answer 26

the amount of energy required to move an electron from an individual atom in the gas phase. - metals have low ionization energy, they easily lose electrons, to be cations. - non-metals have high ionization energies because they do not want to lose electrons, but gain electrons to form a full octet. - ionization energy decreases as you go down a groups of the periodic table - ionization energy increases as you go across a period of the periodic table.

Question 27

Atomic radius

Answer 27

- the relative size of an atom - as you go down a group the atomic radius increases because you are adding more energy levels. - as you go across a period the atomic radius decrease. You increase the number of protons in the nucleus. So the electrons are held more closely to the nucleus when in the same energy level.

Question 28

cation lose electrons

Answer 28

so they are smaller than the atom.

Question 29

anions gain electrons

Answer 29

the radius is bigger than the atom.

Question 30

exothermic processes

Answer 30

``` making ice cubes formation of snow in clouds condensation of rain from water vapor a candle flame mixing sodium sulfite and bleach rusting iron burning sugar forming ion pairs combining atoms to make a molecule in the gas phase mixing water and strong acids crystalizing liquid salts (as in chemical handwarmers) ```

Question 31

endothermic processes

Answer 31

``` melting ice cubes conversion of frost to water vapor evaporation of water forming a cation from an atom in the gas phase baking bread cooking an egg producing sugar by photosynthesis separating ion pairs splitting a gas molecule apart mixing water and ammonium nitrate making an anhydrous salt from a hydrate melting solid salts ```