Vlera Ternava
Evaluation: Chemistry
1.) Complete the table
Carbon and oxygen compounds
Compound/ functional group -OH -O- C=O
Alcohol -OH R-OH
Aldehydes and Ketones
Carboxylic acids
Ether
Estes
2.) Complete the oxidation reduction reactions below:
a.) Primary alcohol --> Aldehyde --> Carboxylic acid -- Carboxylic Acid →
Aldehyde → Primary Alcohol
b.) Secondary alcohol: Ketone (because ketones cannot be oxidized further
under normal conditions)
c.) Tertiary alcohol -----> no oxidation reaction (no reduction path)
3.) Write which are primary, secondary, and tertiary alcohols.
Primary secondary tertiary
1.) The –OH is on a carbon bonded to only one other carbon (primary)
2.) The –OH is on a carbon bonded to two other carbons (secondary)
3.) The –OH is on a carbon bonded to three other carbons (tertiary)
4.) Name these organic compounds:
1.) First Structure: Name: 1-Butanol (Butan-1-ol): The hydroxyl (-OH)
group is on carbon 1 of a straight-chain butane (4-carbon) structure.
2.) Second Structure: Name: 2-Butanol (Butan-2-ol): The hydroxyl (-OH)
group is on carbon 2 of a straight-chain butane (4-carbon) structure.
3.) Third Structure: Name: Tert-Butanol (2-Methylpropan-2-ol) The
hydroxyl (-OH) group is on carbon 2 of a straight-chain butane (4-carbon)
structure.
Yes! All three compounds are alcohols because they contain the hydroxyl (-
OH) functional group attached to a saturated carbon. Alcohols follow the
general formula R-OH.
5.) Name the examples below:
1.) Formic acid
2.) Acid aldehyde
3.) acetone
4.) acitic acid
5.) ethyl acid
6.) Write the molecular formula of formaldehyde and explain its properties?
The molecular formula of formaldehyde is CH₂O. It is the simplest aldehyde
with the structural formula:
H- C(=O)−H
Colorless gas
Odor: Pungent, strong smell
Solubility: Highly soluble in water, forming formalin (a 37% aqueous
solution).
Highly Reactive: Due to the presence of the carbonyl (-CHO) functional
group.
Preservative: Used in formalin for biological specimen preservation.
Disinfectant: Used in sterilization and fumigation.
Resin Manufacturing: Produces Bakelite, urea-formaldehyde,
and phenol-formaldehyde resins.
Highly toxic and can cause irritation to the eyes, nose, and throat.
Carcinogenic: Prolonged exposure may lead to health risks.
7.) Name the compounds:
1.)
2.)
3.)
8.) Explain the uses and the properties of: formic, ethanoic, and citric acids?
1.) Formic Acid:
Properties:
Simplest carboxylic acid.
Stronger acid than acetic acid.
Pungent odor and is highly corrosive.
Uses:
Preservative & antibacterial agent in livestock feed.
Textile & leather industries for dyeing and tanning.
Agriculture as a pesticide and in silage preservation.
2.) Ethanoic Acid:
Properties:
Organic acid with a sharp vinegar-like smell.
Weak acid but capable of reacting with bases, metals, and carbonates.
Uses:
Food industry as vinegar (5-8% acetic acid solution) for flavoring and
preservation.
Chemical industry in the production of synthetic fibers, plastics, and
adhesives.
3.) Citric Acid:
Properties:
Weak organic acid with three carboxyl groups (tricarboxylic acid).
Naturally found in citrus fruits (lemons, oranges).
Readily soluble in water.
Uses:
Food & beverage industry as a natural preservative and flavor
enhancer.
Pharmaceuticals for effervescent tablets and pH regulation.
Cleaning products to remove hard water stains and rust.
9.) Explain the difference in melting and boiling points between alcohols and
carboxylic acids?
Carboxylic acids have higher melting and boiling points than alcohols of
similar molecular weight due to stronger hydrogen bonding and dimer
formation.
10.) Ethers are used to extract non polar solvents, explain why?
Ethers are used to extract non-polar solvents because they are relatively
non-polar themselves and can dissolve non-polar substances without forming
strong intermolecular interactions.
11.) Write the reaction of ether formation.
The formation of an ether is typically done through the Williamson ether
synthesis. The reaction is as follows:
R-X + R'-O⁻ → R-O-R' + X⁻
Where:
R-X is an alkyl halide.
R'-O⁻ is an alkoxide ion (from an alcohol).
R-O-R' is the ether product.
X⁻ is the halide ion (e.g., Cl⁻, Br⁻, or I⁻).
12.) Waxes are lipid compounds, and they are in solid state because they have long-
chain hydrocarbons or esters that have strong intermolecular forces, which make them
solid at room temperature.
13.) The rules for naming esters are as follows:
1. Identify the alkyl group from the alcohol part (the part derived from
the alcohol). This comes from the portion attached to the oxygen atom.
Example: In ethyl acetate (CH₃COOCH₂CH₃), the "ethyl" comes from
the alcohol (ethanol, C₂H₅OH).
2. Name the acid part by replacing the "-ic acid" suffix of the parent
carboxylic acid with "-ate."
Example: In ethyl acetate, the "acetate" comes from acetic acid
(CH₃COOH).
3. Put the alkyl group name (from the alcohol) first, followed by the
name of the acid part (with the "-ate" suffix).
Thus, ethyl acetate is named from ethanol (ethyl) and acetic acid (acetate).
