what amount of ethanol is needed for combustion reaction for a 20 oz bottle?

20 oz bottle of what?

Here is a worked example but first convert 20 oz of whatever it is to grams.
1 oz = about 28.3 grams.

20 oz bottle of what?

Here is a worked example but first convert 20 oz of whatever it is to grams.
1 oz = about 28.3 grams.
http://www.jiskha.com/science/chemistry/stoichiometry.html

To determine the amount of ethanol needed for a combustion reaction in a 20 oz bottle, you need to know the concentration of ethanol in the solution and the stoichiometry of the combustion reaction.

Step 1: Determine the concentration of ethanol
- The concentration of ethanol is typically expressed as a percentage by volume or weight. For example, if the concentration is given as 40% ethanol by volume, it means that 40% of the solution volume is ethanol.
- Convert the concentration to a decimal by dividing the percentage by 100. In this case, 40/100 = 0.4.

Step 2: Calculate the amount of ethanol
- Multiply the volume of the bottle (20 oz) by the concentration of ethanol. This will give you the volume of ethanol in the bottle.
- For example, if the concentration is 0.4 and the bottle volume is 20 oz: 0.4 * 20 = 8 oz of ethanol.

Note: If the concentration is given as a percentage by weight, you may need to convert it to a volume percentage, which requires additional information about the density of the solution.

It is important to remember that combustion reactions should be performed with caution, following proper safety guidelines and in controlled environments.