The optimal pH is 6.9. The pancreatic amylase is a hydrolase secreted by pancreas and will go into the alimentary canal. The working environment has a pH of 6.9. So the optimal pH for the enzyme needs to be 6.9.
Avogadro's number represents the number of units in one mole of any substance. This has the value of 6.022 x 10^23 units / mole. This number can be used to convert the number of atoms or molecules into number of moles. We calculate as follows:
237g CCl4 (1 mol / 153.81 g ) (6.022 x 10^23 molecules / 1 mol ) = 9.28x10^23 molecules
1. the Moon must be in line with the Earth and Sun - New Moon for a solar eclipse and Full Moon for a lunar eclipse.2. the Moon must be at one of its nodes. Most of the time the Moon at New or Full passes above or below the Sun because its orbit is tilted relative to the ecliptic. An eclipse can occur only when it is at a node, in other words crossing the ecliptic.
Incomplete question. Full question reads;
Darwin developed the theory of evolution to explain why there are so many different kinds of living things. He could easily observe that offspring of any animals were slightly different from their parents and that this could allow for big changes over thousands of years. He did not know that genes caused the differences. Genes are now very important in the modern theory of evolution.
What most likely led to a change in the widely accepted theory of evolution?
Answer:
<u>new experiments involving genes and evolution </u>
<u>Explanation:</u>
Indeed, the original theory of evolution has experienced several changes in its acceptance because of its imperfect and wrong assumptions not based on generally acceptable scientific facts,
Hence, new experiments involving genes and evolution has led to a change (disagreements and few agreements) in the widely accepted theory of evolution.
The formula for mole fraction is:
-(1)
The solubility of oxygen gas = 1.0 mmol/L (given)
1.0 mmol/L means 1.0 mmol are present in 1 L.
Converting mmol to mol:
![1.00 mmol\times \frac{1 mol}{1000 mmol} = 0.001 mol](https://tex.z-dn.net/?f=1.00%20mmol%5Ctimes%20%5Cfrac%7B1%20mol%7D%7B1000%20mmol%7D%20%3D%200.001%20mol)
So, moles of oxygen = 0.001 mol
For moles of water:
1 L of water = 1000 mL of water
Since, the density of water is 1.0 g/mL.
![Density = \frac{mass}{volume}](https://tex.z-dn.net/?f=Density%20%3D%20%5Cfrac%7Bmass%7D%7Bvolume%7D)
![Mass = 1.0 g/ml\times 1000 mL = 1000 g](https://tex.z-dn.net/?f=Mass%20%3D%201.0%20g%2Fml%5Ctimes%201000%20mL%20%3D%201000%20g)
So, the mass of water is 1000 g.
Molar mass of water = 18 g/mol.
Number of moles of water = ![\frac{1000 g}{18 g/mol} = 55.55 mol](https://tex.z-dn.net/?f=%5Cfrac%7B1000%20g%7D%7B18%20g%2Fmol%7D%20%3D%2055.55%20mol)
Substituting the values in formula (1):
![mole fraction = \frac{0.001}{55.55+0.001}](https://tex.z-dn.net/?f=mole%20fraction%20%3D%20%5Cfrac%7B0.001%7D%7B55.55%2B0.001%7D)
![mole fraction = 1.8\times 10^{-5}](https://tex.z-dn.net/?f=mole%20fraction%20%3D%201.8%5Ctimes%2010%5E%7B-5%7D)
Hence, the mole fraction is
.