i had a lab that combined
1/2 cup of H2O2 (118.3 ml)
and 2 tsp of yeast.
is the equation for the reaction
2H2O --> 2H2O + O2
what would the mass be for each product
in the reation? Is the density of
H2O2 1.4g/ml?
Here is some interesting reading on this subject. As to the mass of each product, simply use regular stoichiometric procedures. The density of H2O2 depends upon the concentration.
For a more indepth discussion, read more than just the first response.
http://www.newton.dep.anl.gov/askasci/gen01/gen01340.htm
To determine the equation for the reaction between hydrogen peroxide (H2O2) and yeast, you need to understand that yeast contains enzymes called catalases that break down hydrogen peroxide. The reaction equation can be represented as:
2 H2O2 (hydrogen peroxide) → 2 H2O (water) + O2 (oxygen gas)
In this reaction, hydrogen peroxide decomposes into water and oxygen gas. The equation you provided is incorrect because it shows both sides of the equation having hydrogen peroxide.
Now, to calculate the mass of each product, you would use stoichiometry. The balanced equation allows you to determine the molar ratio between the reactant and products. The molar ratio gives you the conversion factor to calculate the mass of a substance.
In this case, the molar ratio between H2O2 and O2 is 2:1. This means that for every 2 moles of hydrogen peroxide, you get 1 mole of oxygen gas. Since the reaction uses 1/2 cup of H2O2 (118.3 mL), you need to convert this volume to moles using the density of H2O2.
Given the density of H2O2 as 1.4 g/mL, you can calculate the mass of hydrogen peroxide as follows:
Mass of H2O2 = Volume of H2O2 × Density of H2O2
= 118.3 mL × 1.4 g/mL
= 165.62 g
To calculate the mass of each product, you need to use the molar mass of each substance. The molar mass of H2O is approximately 18 g/mol, and the molar mass of O2 is approximately 32 g/mol.
For water:
Mass of H2O = (Molar ratio of H2O : H2O2) × Mass of H2O2
= (2 mol H2O / 2 mol H2O2) × 165.62 g
= 165.62 g
For oxygen gas:
Mass of O2 = (Molar ratio of O2 : H2O2) × Mass of H2O2
= (1 mol O2 / 2 mol H2O2) × 165.62 g
= 82.81 g
Therefore, in this reaction, the mass of water produced would be approximately 165.62 grams, while the mass of oxygen gas produced would be approximately 82.81 grams.
Remember to always double-check your calculations and pay attention to the significant figures.