Aula 02 - Covid 19 e Álcool70.

Summary

This educational video explains the various forms and uses of alcohol, including hydrated and anhydrous alcohol. It covers how alcohol concentrations are measured in volume or mass percentages, and how these are used in products like beverages, hand sanitizers, and fuel. The video also highlights the role of alcohol in sanitization, specifically how ethanol interacts with bacteria and viruses by denaturing proteins. The importance of using the correct alcohol concentration, such as 70% alcohol in sanitizers, is emphasized for effective disinfection. Overall, it provides insight into alcohol’s chemical properties and practical applications.

Takeaways

• 😀 Alcohol is a mixture of ethanol and water, forming a true solution where the particles are less than a nanometer in size.
• 😀 Alcohol concentration can be expressed in volume percentage or mass percentage, with volume percentage being more common for alcoholic beverages.
• 😀 '54° GL' indicates a 54% alcohol by volume concentration, while '80° INPM' indicates 80% alcohol by mass.
• 😀 When referring to alcohol concentrations, the units used (ml, grams, or kilograms) must match the type of measurement (volume or mass).
• 😀 Ethanol (ethyl alcohol) is the type of alcohol commonly used in beverages, as a fuel, and as a disinfectant.
• 😀 Anhydrous alcohol (without water) is almost pure ethanol, while hydrated alcohol contains water mixed with ethanol.
• 😀 Alcoholic beverages like beer, wine, and spirits vary in alcohol content, with beer around 9%, wine up to 14%, and stronger liquors like cachaça around 48%.
• 😀 Alcohol 70° GL refers to a mixture where 70% of the volume is alcohol, commonly used in hand sanitizers and disinfectants.
• 😀 The use of 70% alcohol is important because it slows evaporation, increasing the time it remains effective against microorganisms on the skin.
• 😀 Alcohol interacts with proteins in microorganisms, causing denaturation, which effectively destroys their function and kills bacteria and viruses.

Q & A

What is the difference between hydrated alcohol and anhydrous alcohol?

Hydrated alcohol is a mixture of alcohol and water, forming a true solution, whereas anhydrous alcohol is alcohol without water, often near 99.99% purity.

What does the percentage written on an alcohol bottle represent?

The percentage on an alcohol bottle represents the alcohol concentration either by volume (e.g., 54° GL means 54% alcohol by volume) or by mass (e.g., 80° ENM means 80% alcohol by mass).

What is the significance of the term 'GL' and 'ENM' on alcohol packaging?

'GL' refers to the percentage of alcohol by volume, while 'ENM' refers to the percentage by mass. GL is used when referring to liquids, while ENM is used for solid or semi-solid alcohol products.

How is the alcohol content in beverages like beer and wine typically measured?

Alcohol content in beverages is usually measured as a percentage by volume. For example, beer can be around 9%, wine can go up to 14%, and spirits like cachaça can reach 48% alcohol by volume.

Why is it necessary to use anhydrous alcohol in fuel mixtures like ethanol?

Anhydrous alcohol is used in fuel mixtures because water is not soluble in gasoline, and its presence would cause significant issues, such as improper fuel combustion.

What role does water play in alcohol gel products?

Water acts as a solvent in alcohol gel, allowing the alcohol to remain in gel form and facilitating the gel's application while also reducing its evaporation rate.

Why is alcohol typically used in disinfectants like alcohol gel?

Alcohol, especially at 70% concentration, is effective in killing bacteria and viruses by denaturing their proteins, thereby disrupting their function and causing them to lose their ability to infect.

Why is a 70% concentration of alcohol considered optimal for disinfecting?

A 70% alcohol concentration is ideal because it evaporates slowly enough to remain in contact with microorganisms for longer, enhancing its ability to denature proteins and effectively kill bacteria and viruses.

What happens when alcohol interacts with proteins in microorganisms?

Alcohol denatures the proteins in microorganisms by altering their three-dimensional structure. This process deactivates the microorganisms, rendering them incapable of performing their necessary functions.

What is the difference between alcohol used for disinfecting and alcohol used for fuel?

Alcohol used for disinfecting is typically ethanol or isopropyl alcohol diluted with water for safety and effectiveness in killing microbes, while alcohol for fuel, like anhydrous ethanol, is used in its purer form for combustion in engines.