Acids and bases

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Pages 21, 22, 23

Properties

Taste

Feel

Conductivity

Reacts with metals

(yes or no?) what products?

pH range

Acids

Sour

Yes

Yes- forms H

0-7

2 gas

Bases

Bitter

Slippery

Yes

No

7-14

-

-

Hydrogen + a polyatomic?

Polyatomic ends in –ate the acid ends in –ic

Polyatomic ends in –ic the acid ends in –ous

-

Hydrogen + a single element?

Hydro______ ic acid

a) HCl – Hydrochloric acid b) HF – Hydrofluroic acid c) HNO

2

Nitrous acid d) H

2

SO

4

– Sulfuric acid

If the acids ends in an “ic” then the polyatomic ends in the –ate form

If the acids ends in “ous” then the polyatomic is in the – ite form

If the acid starts in Hydro- then the formula is

Hydrogen followed by the element ending in – ide

Hydrochloric acid= HCl

a) nitric acid HNO

3 b) acetic acid – HC

2

H

3

O

2 c) hydrobromic acid HBr d) sulfurous acid – H

2

SO

3

Following ionic naming rules

Name the cation regularly, the polyatomic uses its regular name.

a)KOH Potassium hydroxide b) Ba(OH)

2

Barium hydroxide c) LiOHLithium hydroxide d) NH3 – ammonia

Use ionic rules

Write the symbols.

Identify the charges- criss cross to make subscripts.

 a) Sodium hydroxide NaOH

 b) Beryllium hydroxide Be(OH)

2

 c) Calcium hydroxide Ca(OH)

2

 d) Cesium hydroxide CsOH

Arrhenius acid- contains an H+

Bronsted- Lowry acid- Donates an H+

Arrhenius base- contains an OH-

Bronsted- Lowry base- Accepts an H+

HNO

3

+ H

2

O  H

3

O + + NO

3

-

ACID BASE ACID BASE

N

2

H

4

+ H

2

O  N

2

H

3

+ H

3

O +

ACID BASE BASE ACID

N

2

H

4

+ HCl  N

2

H

BASE ACID ACID

5

+ + Cl -

BASE

Neutralization reactions:

ACID+ BASE  SALT + WATER

KOH + H

2

CO

3

KOH + H

2

CO

3

 H

2

O + K

2

CO

Don’t forget to BALANCE!

3

2 KOH + H

2

CO

3

 2 H

2

O + K

2

CO

3

HBr + Al(OH)

3

HBr + Al(OH)

3

3 HBr + Al(OH)

3

 H

2

O + AlBr

3

 3 H

2

O + AlBr

3

[H+]

1.

2.3x10

-5 M

2.

5.0x10

-8 M

3. 1.2x10

-11 M pH

4.64

7.3

10.9

[OH-] pOH

4.3x10

-10 M 9.36

2.0x10

-7 M 6.7

8.1x10

-5 M 3.1

Acid, base, neutral?

Acid

Base

Base

Titration- method for determining concentration of a solution by reacting a known volume of solution with a solution of known concentration

Equivalence point- equal amounts of OH -

& H + ions

Pages 24

94. Chemical and Nuclear Reaction

Radiation Type Alpha Beta Gamma

Charge

Description

Symbol

Mass

Penetrating Power

Shielding Needed

+2 -1 0

Helium nucleus electron EMR

4

2 a or

4

2

He 0

-1 b or

0

-1 e g

4 amu 1/1840 amu 0 low medium high

Paper, cloth, skin, etc.

Aluminum foil Lead

Beta decay = electron

191 is gold’s Atomic mass, which goes on top.

Look up Gold (Au) on your periodic table to find the atomic number which goes on the bottom.

Gold’s atomic number is 79.

191

79

Au  0

-1 e +_____

191

79

Au  0

-1 e + 191

80

Hg

 alpha decay = helium particle

90 is Rubidium’s Atomic mass, which goes on top.

Look up Rubidium (RB) on your periodic table to find the atomic number which goes on the bottom. Rubidium’s atomic number is 37.

90

37

Rb  4

2

He +_____

90

37

Rb  4

2

He + 86

35

Br

A. 4

2

He + 14

7

N  _____ + 1

1

H

4

2

He + 14

7

N  17

6

C + 1

1

H

B. 102

44

Ru + 4

2

He  1

0 n +_____

102

44

Ru + 4

2

He  1

0 n + 105

46

Pd

Page 25

Potential energy- stored energy due to position

Kinetic energy- energy of motion

*remember that Temperature is a measure of the average kinetic energy

Heat- (Q) = the process of flowing from warmer to colder temperature.

Temperature- measure of the average kinetic energy (KE) in a sample

Specific heat (c) is the amount of energy required to raise the temperature of a 1 gram sample by 1 degree

High specific heat means that the substance warms and cools slowly. It resists changes in temperature.

Low specific heat means that the substance warms and cools quickly.

SI Unit = J/(g·°C)

a . Conduction- heat is transferred by touch.

Ex: heating a pan on the stove b. Convection- heat is transferred through liquids or gases.

Ex: Cooking in an oven c. Radiation- heat from the sun

 a. -200 kJ exothermic

 b. 32 kJ endothermic

 c. 653.8368 kJ endothermic

Exothermic reactions release energy so they lose energy (negative sign)

Endothermic reactions absorb heat so they have energy added (positive sign)

FORMULA: Q=mc∆T

Q= heat(J); m= mass(g); c=specific heat J/(g·°C);

∆T = change in temperature (Final– initial)

Q= (1.05)(.450)(63.5)

Q= 30.0 J

∆T = 88.5-25 = 63.5

The reaction is endothermic because it absorbs heat.

Balance the equation:

1 CH4(g) + 2 O2(g)  1 CO2(g) + 2 H2O(l)

Hrxn = -890.2 kJ/mole

52.4g 1 mol

16.043 g

= 3.27 moles

3.27 mol -890.2kJ

= -2910 kJ

1 mole

Page 26, 27, 28

1. Pressure (P)- atm, torr, kpa, mmHg, psi

2. Volume- (V) Liters

3. Temperature (T)- Kelvin

4. Amount- (n) moles

R = gas constant!

1. Gases consist of molecules whose separation is much larger than the size of the molecules themselves.

2. Particles in a gas move in straight line paths and

random directions.

3. Particles in a gas collide frequently with the sides of the container and less frequently with each other. All collisions are elastic (no energy is gained or lost as a result of the collisions).

4. Particles in a gas do not attract or repel one another. They do not sense any intermolecular forces.

STP = 0 0 C and 1 atm

Temperature in Kelvin = 273K

STP can be found on the STAAR chemistry reference chart under the constants and conversions section.

LAW

BOYLE’S

CHARLES’S

GAY LUSSAC’S

INDEP/DEP

VARIABLES

V, P

T, V

P, T

V, n

AVOGADRO’S

V, P, T,

COMBINED

IDEAL P,V,n, R, T

CONTROL

VARIABLES

T, n

P, n

V, n

P, T

NA

MATH

RELATIONSHIP

↑V, ↓ P inverse, indirect

↑T ↑V direct

↑T ↑P direct

↑n ↑V direct

NA

FORMULA

V

1

P

1

=V

2

P

2

V

1

= V

2

T

1

P

1

T

2

= P

2

T

1

T

2

V

1

= V

2 n

1

P

1

V

1 n

2

= P

2

V

2

T

1

T

2

R PV=nRT

STP= Standard temperature and pressure

P= 1 atm, T= 0 o C or 273K

PV=nRT

(1atm)(V)= (1.02moles)(.0821)(273)

V= 22.8L

STP= Standard temperature and pressure

P= 1 atm, T= 0 o C or 273K

PV=nRT

(1atm)(1.5L)=(n)(.0821)(273)

1.5= 22.4n

n= .067 moles

Molar mass of helium

.067 moles 4.003g

1 mole

= .27 grams

PV=nRT

(.988atm)(1.20L)=(.0470)(.0821)(T)

1.1856= .00385T

308K=T

Convert grams to moles to plug into the ideal gas law equation!

3.58g

1 mol =.177 mol

20.180g

PV=nRT

(.900atm)(V)=(.177mol)(.0821)(287)

V= 4.63L

Comparing Volume and Pressure – Boyles’ law

V

1

P

1

=V

2

P

2

(6L)(101kPa)=(V

2

)(91kPa)

606=(V

2

)(91kPa)

6.7L=(V

2

)

Comparing Volume and pressure- Boyles’ law

V

1

P

1

=V

2

P

2

(2.25L)(164kPa)=(1.50L)( P

2

)

369= (1.50L)( P

2

)

246 kPa=(

P

2

)

Comparing Temperature, volume and

Pressure – Combined gas law

P

1

V

1

T

1

= P

2

V

2

T

2

 (10.5)(.948) = (25.0)(P

2

)

500 618

 .019908= (25.0)(P

2

)

618

12.3= (25.0)(P

2

)

P

2

= .49 atm

Comparing volume and temperature- Charles

(7.36L) = ( V

2

)

(323K) (173K)

( V

2

) = 3.94L

Dalton’s law of partial pressure

*Be sure that all of the pressure values have the same units.

P

TOT

P

TOT

P

TOT

= P

1

+ P

2

+P

3

= 1.2atm +.75atm +.41atm

= 2.36 atm

Dalton’s law of partial pressure

*Be sure that all of the pressure values have the same units.

Convert kPA to atm 101kPa=1atm:

199 kPa 1 atm = 1.97atm

101kPa

P

TOT

= P

1

+ P

2

+P

3

1.97= .59+.65 +P

3

.73atm =P

3

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