Because 70% is a strong enough concentration to lead to the disintegration of the outer bacterial plasma membranes, eventually denaturing proteins and killing off bacteria. We do not tend to use 100% ethanol (one would think it to be more effective) since this could kill off the bacteria, however it may preserve the genetic material of the bacterium, which may be transferred to other bacterial cells. This is to be avoided when culturing cells, for example.
to save the ethanol
70%
49/70 x 100 = 70 percent.
27 percent of 70 = 18.927% of 70= 27% * 70= 0.27 * 70= 18.9
2 percent of 70 =1.42% of 70= 2% * 70= 0.02 * 70= 1.4
70 percent ethanol is more effective at killing microbes than 100 percent ethanol. This is because the addition of water helps to denature proteins and disrupt cell membranes in the microbes, leading to better penetration and more efficient sterilization. Additionally, 70 percent ethanol is less volatile and evaporates more slowly, allowing for longer contact time with the microbes.
Absolutely, recent painstaking scientific research has showed that 70% ethanol is the same as 70% ethanol.
to save the ethanol
70% is the most effective concentration to denature poteins so killing bacteria. At 95% the ethanol just evaporates and leaves the protein untouched. Below 70% does not denature proteins. It also makes the ethanol less flammable.
Seventy percent ethanol is commonly used in RNA extraction to wash and remove salts and contaminants from the RNA sample. It helps to purify the RNA by precipitating it out of the solution while leaving behind impurities. Additionally, the 70% ethanol concentration helps minimize RNA degradation during the extraction process.
150 ml ethanol to 350 ml distilled water
To find the total volume of 70% ethanol, you need to divide the volume of pure ethanol (1600 ml) by the concentration of ethanol (0.70). This gives you a total volume of approximately 2285.71 ml of 70% ethanol.
Disinfectants are usually mostly alcohol, Ethanol to be exact. Ethanol can only reach a purity degree of 95-96 percent in liquid form, with purer solutions existing only as a gas. 70 percent alcohol is sufficient to kill the bacteria, and a higher purity would not have any beneficial effect.
Ethanol creates pores in the cell membrane of the microbial cell by solubilizing the lipoproteins of the membrane. The activity of ethanol determines its concentration. If we 90 percent ethanol, the amount of ethanol molecules available to act upon the cell is more and it attacks the cell membrane from all sides. The dissolved lipoprotein forms a kind of layer around the cell, due to which the alcohol is unable to act further and cause damage to the cell. However, if we use 70 percent ethanol, the amount of ethanol molecules are few and it is not able to attack the cell from all sides. Thus, pores are created intermittently in the plasma membrane, the ethanol penetrates the cell and damages it completely. So, 70 percent ethanol is preferable to 90 percent when using microbial cultures.
70% ethanol is commonly used in laminar air flow chambers because it effectively disinfects surfaces by killing a broad spectrum of pathogens, including bacteria and viruses. The 70% concentration is more effective at penetrating the cell wall of microorganisms compared to higher concentrations of ethanol. Additionally, the lower ethanol concentration helps reduce evaporation, ensuring longer contact time with the surfaces being disinfected.
No, 70 percent ethanol is not effective in disinfecting prions. Prions are highly resistant to common disinfection methods, including alcohol-based solutions. Specialized procedures involving harsh chemicals or autoclaving at high temperatures are required to effectively deactivate prions.
70% alcohol solution is more effective for sterilization compared to higher concentrations like 100% alcohol because it has a lower evaporation rate, allowing it to stay in contact with the bacteria or viruses longer to kill them. A 70% alcohol solution also penetrates the bacterial cell membrane more effectively, denaturing proteins and disrupting cell function. Additionally, 70% alcohol is less likely to damage surfaces or instruments being sterilized.