Acid Base Reactions

Acid Base Reactions
In an Acid Base Reaction, the driving force is the production of water. These reactions will produce a salt and water as products. Salt= cation of base and anion of an acid

A solution of aq nitric acid and aq potassium hydroxide are mixed in a titration
Molecular: HNO3  (aq) + KOH (aq) --> KNO3 + H2O (l)
Net: H+  (aq) + OH-  (aq) --> H2O (l)
Click here for extra help!

Chemical Reactions

Chemical Reactions

Sensory Clues a change is taking place

• color has changed
• a solid forms
• bubbles form (in a liquid)
• Heat and/or a flame is produced, or heat is absorbed

Heat is Enthalpy = H

Delta H = Change in enthalpy

CHEMICAL REACTION LABS!

These are the pictures of products from our chemical reactions lab on Friday.

For help with solubility rules, click here.

Empirical Formulas...

Empirical Formulas
What is % Composition of C10H14O?
Calculate the mass of H in 25.4 g of C10H14O.
C= 10 x 12.01 = 120.1
H= 14 x 1.01 = 14.14
O= 1 x 16 = 16.00

120.1 + 14.14 + 16.00 = 150.24 g/mol

%C= (120.1/150.24)(100)= 79.94% C
%H= (14.14/150.24)(100)= 9.412% H
%O= (16.00/150.24)(100)= 10.65% O

(9.412%)(25.4 g)= 2.39 g H

MOLECULAR FORMULAS
-whole number multiple of empirical formula

• ratio of masses

-Can be the same as the empirical formula

EX: P4O10

EMPIRICAL FORMULAS

-lowest whole number ratio of elements in a compound

-start with % composition and work to moles

EX: P2O5


For more help with empirical formulas, click here!

 

Formula of a Chloride Lab

Formula of a Chloride Lab
Procedure:

1. Determine the mass of a clean, dry 100 mL beaker to the nearest 0.001 g and record this mass on the data table
2. Have your instructor place a small amount of zinc into the beaker. Then determine the mass of the beaker plus zinc and record in the data table.
3. Using a graduated cylinder to measure, add 10 mL 3M HCl. Using a hot plate, gently heat the mixture until all of the zinc has dissolved
4. Using a Bunsen burner, heat the solution until all of the water and excess HCl have been boiled away. Stop the heating as the last bit of liquid disappears. Do not continue heating after it has boiled to dryness as the compound will begin to decompose.
5. Cool for several minutes and then determine the mass of the beaker and contents.

Be careful when working with Chlorine gas... You might end up not feeling well and watching the lab from the hall.

Hydrated Compounds

Hydrated Compounds...

Have water molecules as part of their chemical formula
Contribute to the crystalline structure of the compound

HYDRATED vs ANHYDRIDES

Hydrated end up being ANHYDRIDES, which are chemicals that used to be hydrated.

Ordered (how they're arranged in space)=crystalline

What is the value of "n" for the hydrate of Magnesium Chloride H2O?
Mass of crucible = 22.130 g
Mass of crucible + hydrate = 25.290 g
Mass of crucible + contents after heating = 23.491 g

25.290 g (Cruc + Hyd) - 22.130 g (Cruc) = 3.160 (Hydrate)

23.491 g (after heating) - 22.130 g (crucible) = 1.361 g (Anhydrous)

25.290 g (hydrate) - 1.361 (anhydrous)
= 1.799 g H2O driven off

1.799 g H2O x 1 mol H2O    = .09983 mol H2O
                       18.02 g H2O

1.361 g MgCl2  x  1 mol MgCl2  =  .01429 mol MgCl2
                            95.21 g MgCl2

.09983 mol H2O    = 7
      0.01429
n = 7


Click Here For Extra Help.
Extra help with hydrates can be found here.

Molar Mass

MOLAR MASS is the mass in grams of 1 mole of a substance

• unit= g/mol
• Gram Molecular Mass

1. Covalent Compounds (no metals)

• Gram Formula Mass

1. Ionic Compounds

JUMPING RIGHT IN...

• C3 H8 

C 3 (# in compound)  x 12.01 (Periodic Table) = 36.03

H 8  (# in compound) x 1.01 (Periodic Table) = 8.08

36.03 + 8.08 = 44.11 g/mol 

DIATOMIC ATOMS

H2,       O2,      F2,    Br2,     I2,     N2,      Cl2 

they only double their mass when ALONE

EX: O2 --> (2)(16.00)= 32.00 g/mol

For more Diatomic Atom help, Click Here. 
Watch the video below, or check out this website for more help with molar mass calculations.

(n.d.). Retrieved November 6, 2015, from https://d2gne97vdumgn3.cloudfront.net/api/file/T3WWBj9jQb67Siqvkqi5
(n.d.). Retrieved November 6, 2015, from http://study.com/academy/lesson/diatomic-molecule-definition-example.html
How to Calculate Molar Mass. (n.d.). Retrieved November 6, 2015, from https://www.youtube.com/watch?v=F9NkYSKJifs

Molar Mass of Compounds - Boundless Open Textbook. (n.d.). Retrieved November 6, 2015, from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/mass-relationships-and-chemical-equations-3/molar-mass-41/molar-mass-of-compounds-223-7524/

The Mole

THE MOLE and no, not the animal this time. The mole that we are going to talk about is a quantity of measurement, the 6.02 x 10^23



SOLVING MOLE PROBLEMS...

1. Decide what the question is asking
2. Write down all the given information
3. Label all quantities
4. Solve the Equation

Let's look at the MOLE ROAD MAP to help us solve problems.

FOR EXAMPLE, How many moles of Mg is 3.01 x 10^22 atoms of Mg?
WELL,


3.01 x 10^22 atoms Mg    x                 1 mol Mg                           =    5.00 x 10^-2 mol Mg
                                                    6.02 x 10^23 atoms Mg

For more help understand the MOLE and MOLE PROBLEMS using the MOLE ROAD MAP, you can CLICK HERE! Good luck, and Happy Learning!

The Mole Highway Roadmap. (n.d.). Retrieved November 5, 2015.
(n.d.). Retrieved November 5, 2015, from https://dr282zn36sxxg.cloudfront.net/datastreams/f-d:869497f7016d9cb18cc1266f9c9d6edfc6149b50b3262dd16764aac7+IMAGE_THUMB_POSTCARD+IMA