Sunday, June 1, 2014

Life Update


So I have made my final decision about this part of my life...I am moving to Curacao. 

I will be leaving for the states June 25th. I'll be bringing my dog with me because my parents are going to watch her for me while I'm there. I will be there for 8 months, and then move back to the states for my internado. I will hopefully be able to come back to the DR to visit. 

I have been so honored to be your teacher this year and will miss you all so much. If you want to follow my future adventures, I have another blog with occasional updates about my life and where I am at. Here is the link to my other blog Kaitlyn's Adventures. Otherwise, feel free to email me if you miss me or have questions: kaitlyn.cunningham@icloud.com or nyltiak@gmail.com.

Thank you for everything this year. I will never forget this experience. 

Miss Cunningham

Answers to Practice

Good afternoon all,

Here are the answers to the practice. I also have a list of the equations that you are allowed to bring to the final. You can bring a the equations for the pH chapter and titration.

Let me know if you have any questions about the practice. Email me at kaitlyn.cunningham@icloud.com or nyltiak@gmail.com with any questions.









Tuesday, May 20, 2014

Practice for Final Exam

  1. 9.35g of Al2O3 contains how many molecules?
  2. 0.253 moles of BN has a mass of…
  3. Calculate the number of moles of 8.46 x 1024 atoms of F.
  4. Calculate the number of moles of 4.35g of Cs2CO3.
  5. 0.692moles of CsH contains how many molecules?
  6. How many moles are in 14.49 g of CoSO4.
  7. What is the mass of 7.20 x 1023 atoms of Ne?
  8. 50.82 g of Cr2O3 has how many moles?
  9. 2.84 moles of N2H4 has how many molecules?
  10. 5.29 x 1024 molecules of HCl has a mass of…
  11. In a 30.0 g sample of Pb(NO3)2, Pb has a mass of 2.535 g, N a mass of 8.694 g, and O a mass of 18.768 g. What is the % composition?
  12. In a 25.0 g sample of Hg2Cl2, Hg has a mass of 3.755 g and Cl has a mass of 21.245 g. What is the % composition.
  13. In a 20.0 g sample of Ni(NO3)2, Ni has a mass of 3.066 g, Ni has a mass of 6.426 g, and O has a mass of 10.508 g. What is the % composition?
  14. What is the % composition of the following:
    • KMnO4
    • Sc2O3
    • H2SeO4
    • Cl3HSi
    • NaBrO
  15. What volume of 0.075 M HCl is required to neutralize 100 mL of 0.01 M NaOH solution?
  16. What is the concentration of NaOH if 45.2 mL of 1.5 M H2SO4 is needed to neutralize 20.0 mL of NaOH: H2SO4 + 2NaOH ➝ Na2SO4 + 2H2O?
  17. Find the [H3O+] and pH of the following: 0.075 M HCl 
  18. Find the [H3O+] and pH of the following: 0.122 M H2SO4
  19. Calculate the [H3O+] and pOH of the following solution: pH = 9.5
  20. Calculate the [H3O+] and pOH of the following solution: [OH-] = 3.9 x 10-12
  21. Find the [OH-] of the following solutions: pOH = 1.5, pH = 4.6, & [H3O+] = 2.5 x 10-9
  22. In the following chemical reactions, identify the acid, base, conjugate acid, and conjugate base.
    • HC2H3O2 + H2O ⇌ H3O+ + C2H3O2-
    • NH3 + H2O ⇌ NH4+ + OH-
    • HNO3 + H2O ⇌ NO3- + H3O+
  23. Find the [H3O+] and pH of the following:
    • 0.025 M HNO3
    • 3.4 x 10-4 M H2SO4
  24. Calculate the [H3O+] and pOH of the following solutions:
    • pH = 3.2
    • pH = 5.0
    • [OH-] = 8.2 x 10-9
    • pH = 12.4
  25. Find the [OH-] of the following solutions:
    • [H3O+] = 3.9 x 10-6 M
    • [H3O+] = 0.0014 M
    • pH = 4.2
  26. If 35.2 mL of 12M HCl is used to titrate 50.0 mL of KOH, what is the concentration of the KOH?
  27. What is the volume of 2.5 M NaOH needed to titrate 25.0 mL of 1.0 M HCl?
  28. Given the following equation, find the concentration of NaOH when 24.09 mL of 1.605 M H2SO4 is needed to titrate 50.0 mL of NaOH.      H2SO4 + 2NaOH ➝ Na2SO4 + 2H2O
  29. What is the salt that is formed during the following neutralization reactions?
    • Mg(OH)2 + HCl ➝ ? + H2O
    • H2SO4 + 2NH4O ➝ ? + 2H2O
    • Ni(OH)2 + 2HClO4 ➝ ? + 2H2O
    • Mg(OH)2 + H2SO4 ➝ ? + 2H2O
  30. Balance the following redox reactions:
    • Na + H2O → NaOH + H2
    • HCl + HNO3 → HOCl + NO + H2O (*Cl on the product side has an oxidation number of +1)
    • SnCl4 + Fe → SnCl2 + FeCl3
    • CO + I2O5 → I2 + CO2
    • MnO4- + Fe2+ + H+ → Fe3+ + Mn2+ + H2O
    • Cu+ + Fe → Fe3+ + Cu

Tuesday, May 6, 2014

Proteins and Nucleic Acids

Proteins
  • Most important substance in the bodies of living things.
  • Building blocks for muscle, hair, blood cells, skin, slk, enzymes, insulin, etc.

Amino Acids
  • Building blocks of proteins.
  • Contain an amine (NH2) group and carboxyl (COOH) group.
  • Various side chains (R groups) attach to the carbon adjacent to the N.
  • Results in 20 different common amino acids.
  • Our bodies can synthesize 12 out of 20.
    • The other 8 must come from diet
    • Known as essential amino acids
List of Amino Acids


Polypeptide Chains

  • Amino acids joined together with peptide bonds.
  • Dipeptides: two amino acids joined together
    • Aspartame (artificial sweetener)
  • Polypeptides: polymers of many amino acids
Polypeptide chain or protein

Proteins
  • Polymer of one or more polypeptide chains.
  • Some contain several hundred amino acids others several thousand.
  • Various structures
Nucleic Acids

DNA Structure
  • When cells reproduce, they pass genetic information to one another in long-chain molecules called chromosomes.
  • Human body contains 46 chromosomes in the nuclei.
  • Segments of chromosomes, called genes, carry the coded information to that directs the production of specific polypeptide chains.
  • Nucleotides are the building blocks of nucleic acid.
    • Three units:
      • 5 carbon sugar (ribose or dioxyribose)
      • phosphate group
      • ring-shaped nitrogen containing base
  • There are five possible nitrogen-congaing bases attached to the sugar:
    • Adenine (A)
    • Cytosine (C)
    • Guanine (G)
    • Thymine (T)
    • Uracil (U)
  • DNA has A, C, G, T
  • RNA has A, C, G, U
  • DNA is two strains coiled around each other in a double helix
  • When cells divide, a DNA strand reproduces by first unraveling with the help of enzymes. 
  • Each of the two resulting strands serves as a template, or pattern, for a new complementary chain.
  • Complementary bases on the newly forming strand match the now-exposed bases of the old strand.
  • When the process of replication is completed, two identical double-stranded DNA molecules result. 
DNA Replication

  • One strand goes to each half of the dividing cell.
  • DNA and RNA molecules instruct cells on how to make proteins.
    • DNA is used as a template to make RNA.
    • RNA is made up of nucleotides.
    • Trinucleotide groups (3 nucleotides) code for various amino acids.
    • As the amino acids join together, they form proteins. 
    • The proteins are the chemical manifestation of our physical characteristics. 
This is an example of protein synthesis from RNA

Differences between DNA and RNA
  • DNA
    • the sugar is deoxyribose
    • contains thymine
    • double strand
  • RNA
    • the sugar is ribose
    • contains uracil
    • single strand

Carbohydrates


  • Most abundant biological compounds.
  • Sugars and starches make up a large part of the human diet.
  • Each year photosynthetic processes in plants convert water and carbon dioxide into one hundred billion tons of carbohydrates.
  • Exoskeletons of insects are made of carbohydrates.

  • All carbohydrates have several of the –OH (hydroxy) groups common to alcohols.
  • They also have the C=O (carbonyl) group of aldehydes and ketones.
  • They are known as one or more polyhydroxy aldehyde or ketone
  • Three main functions:
    • energy storage
    • an energy source for cellular functions
      • glucose
    • structural elements in plants and animals
      • cellulose & chitin
  • Classified into three groups based on the number of sugar units they contain.
    • Monosaccharides 
    • Disaccharides
    • Polysaccharides
Monosaccharides
  • These are simple sugars. One polyhydroxy aldhyde or ketone.
  • Rarely occur in nature by themselves.
  • Usually bonded to an protein, fat or other carbohydrate.
  • Glucose is the most abundant sugar in nature.
  • The human body maintains a reasonably constant level of 80 to 120 mg of glu- cose per 100 mL of blood.
  • Glucose is also the fundamental building block of the most common long-chain carbohydrates.
  • Glucose in an aqueous solution exists in an equilibrium between the ring form and the straight-chain form.
  • Fructose also forms ring structures when it is in solution.
  • Since the carbonyl group is not at the end of the carbon chain, it forms a five-member ring.

Disaccharides
  • Contain two monosaccharide units.
  • An oxygen bridge between the two monosaccharides holds the two units together.
  • Three disaccharides play an important part in the human diet—maltose, lactose, and sucrose.
    • Maltose (glucose - glucose)
      • germinating grain & digestion of starches
    • Lactose (glucose - galactose)
      • milk
    • Sucrose (glucose - fructose)
      • table sugar, fruits, sugar cane, beets, nectar

Polysaccharides
  • Many sugar units, up to several million units
  • Can be built with several different monosaccharide units
  • Glycogen: energy storage 
  • Cellulose: gives plants structure
  • Starch: supply nearly 3/4ths of the worlds food energy

Tuesday, April 29, 2014

Quiz on Wednesday

Study:

  • Difference between aliphatic and aromatic
  • Difference between alkanes, alkenes, alkynes
  • What is a organic compound
  • What is unique about carbon
  • Nomenclature

Hydrocarbons

What are hydrocarbons?

  • The simplest aliphatic and aromatic compounds
  • Only contain hydrogen and carbon
  • Can contain single, double, or triple bonds
  • Classified by the types of bonds.
Alkanes

  • Alkanes are aliphatic hydrocarbons that only contain single bonds.
  • The general formula for alkanes is CnH2n+2
    • Example: CH4, C2H6, C3H8
  • Considered saturated because carbon is surrounded by the max number of hydrogen.
  • Methane is the simples alkane (CH4)
  • Each consecutive alkane adds a carbon and its respective hydrogens.
    • Methane: 1 carbon
    • Ethane: 2 carbons
    • Propane: 3 carbon
    • Butane: 4 carbons
  • Properties of Alkanes
    • Very low melting and boiling points. They rise as carbons are added.
      • Ex. methane
        • Melting point (C):  -183
        • Boiling point (C): -164
    • Non-polar
Alkenes
  • Hydrocarbons that contain double bonds between carbon atoms
  • Contain the prefix -ene.
  • The smallest is ethene. Why not methene?
  • Considered unsaturated, because the double bond prevents the max number of hydrogen from bonding.
  • Naming of alkenes requires numbering the carbons to identify the place where the double bond is.
  • You start at the carbon that will give you the smallest number.
  • This allows us to know where the double bond is. 
  • Properties of Alkenes:
    • Slightly higher melting/boiling points
    • The first couple are gases at room temperature
    • Relatively non polar
Alkynes
  • Hydrocarbons that contain triple bonds between the carbon atoms
  • Uses the prefix -yne
  • The simplest is the most common, ethyne (acetylene).
Cyclic Aliphatic Compounds
  • Not all hydrocarbons are open chains of carbon atoms.
  • Some form a ring.
  • 5 and 6 alkane rings are most abundant. 
  • Some can have more than one double bond.
Aromatic Structures
  • All contain a form of a molecule benzene
  • They are called aromatic because they often smell good
  • C6H6 is the simplest aromatic compound known
  • It was hard to figure out the structure:
    • Behaves like an alkane, but they knew from the molecular weight that it had several double and triple bonds.
    • When they measured the bond length, the found that it should contain 1.5 bond lengths.
    • Showed that carbon was in a ring and all had identical bonds
  • In 1865, August Kekule proposed the structure. 
  • He said that it was a dynamic equilibrium of the two.
  • The double bonds were not “tied dow”, but are more or less shared.