Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
IB Chemistry 2: Depressants
Transcript of IB Chemistry 2: Depressants
A breathalyzer contains crystals of potassium dichromate(VI) which are orange, but are changed to green chromium(III) ions as they oxidize the ethanol to ethanal and ethanoic acid. The extent of the color change can be measured using a photocell and so the ethanol concentration can also be used.
The test is not very accurate. Breathalyzer Different molecules cause different absorption bands in the infrared part of the spectrum, as a result of vibrations of their particular bonds and functional groups. An intoximeter can be used to measure the size of the peak, and thus ethanol concentration, in comparison to a reference take from ambient air.
Another type of intoximeter uses a fuel cell. A catalyst is present to oxidize ethanol in the air first to ethanoic acid and then to water and carbon dioxide. The fuel cell converts the energy released into a detectable electrical voltage that can be used to measure ethanol concentration very accurately. Infrared
Spectroscopy This technique must be carried out in a lab. A sample of blood or urine is vaporized and injected into a stream of an inert gas (the mobile phase) over the surface of a non-volatile liquid (the stationary phase).
The components of the vapor, including ethanol gas, move at different rates depending on their boiling points and relative solubility in the two phases. As a result, each leaves the column holding the liquid phase after a specific interval of time known as its retention time.
So a peak at the retention time corresponding to ethanol can be used to confirm its presence in the vapor. The area under the peak is a measure of ethanol concentration relative to a known standard in the mixture such as propan-1-ol. The method allows for an accurate assessment of ethanol levels. Gas-Liquid
Chromatography N N R O N + O O - D.4.2 Discuss the social
and physiological effects of
the use and abuse of ethanol. Impact on Family Synergistic Effects 1
4 Violent behavior associated with domestic abuse and family breakdown.
Economic cost of alcoholism. With aspirin, ethanol can cause increased bleeding of the stomach lining and increased risk of ulcers With other depressants and sleeping pills, ethanol can induce heavy sedation, possibly leading to coma. With tobacco, ethanol appears to increase the incidence of cancers, particularly of the intestines and liver. With many other drugs, ethanol can interfere with their metabolism by the liver, which can cause greater and more prolonged drug effects. Diazepam
(Mogadon) Fluoxetine Hydrochloride
(Prozac) Cost to Society Dangerous risk-taking behavior leading to many accidents involving motor vehicles and machinery. Short-term Effects on Health Loss of self-restraint; memory, concentration and insight impaired
Loss of balance and judgement
Dehydration caused by increased urine output leading to 'hangover' and loss of productivity.
At high doses, can cause vomiting, loss of consciousness, coma and death. CH C H 3 Effects of Depressants At low to moderate doses, depressants are classified as tranquilizers and can cause calmness, relief from anxiety, and very relaxed muscles. O At high doses, depressants are classified as sedatives and can cause slurred speech, staggering gait, altered perception, and induce sleep. Long-Term Effects on Health Cr CrO At extremely high/lethal doses, depressants are classified as hypnotics and can cause respiratory depression, coma, and death. 3+ Dependence known as alcoholism, associated with withdrawal symptoms.
Liver disease, e.g. cirrhosis, liver cancer.
Coronary heart disease.
High blood pressure.
Fetal alcohol syndrome.
Permanent brain damage. + 2 7 2 - D.4.5 Common Depressants Presentation by:
Harrison Le D.4.1 Uses of Ethanol Present in beer, wine, and hard liquor
Has some antiseptic qualities, so can be used on the skin before an injection or to clean a small wound
Has the effect of hardening the skin. For example, it can be rubbed onto the feet to prevent blisters
Ethanol in alcoholic drinks is an important part of many diets and cultures
There is some evidence that low doses of ethanol might have a beneficial effect on blood circulation and diminish cardio-vascular diseases, perhaps owing to its mild anti-clotting effect
In low doses, it can help to create mild excitement and users become more talkative, confident, and relaxed NH Cl CF O R 3 Metabolism of Ethanol Following ingestion, ethanol passes quickly from the gut into the blood through the stomach wall and then circulates to all tissues of the body Approximately 90% of an ethanol load is broken down in the liver with the remaining being eliminated by the kidneys and lungs. N N O Cl R CH 2 CH 2 2 + - Drugs that act on the brain and spinal cord Benzodiapines are a major group of depressants used as tranquilizers to treat anxiety disorders and insomnia.
The name "benzodiazepine" implies that the molecular structure includes benzene rings and a diazepine structure.