Answer:
1000 times.
Explanation:
Hello,
In this case, since the pH is defined by:
![pH=-log([H^+])](https://tex.z-dn.net/?f=pH%3D-log%28%5BH%5E%2B%5D%29)
If we want to compute the concentration of hydrogen we must write:
![[H^+]=10^{-pH}](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D10%5E%7B-pH%7D)
Thus, for both the backyard soils we compute:
![[H^+]_{pH=7}=10^{-7}=1x10^{-7}M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D_%7BpH%3D7%7D%3D10%5E%7B-7%7D%3D1x10%5E%7B-7%7DM)
![[H^+]_{pH=4}=10^{-4}=1x10^{-4}M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D_%7BpH%3D4%7D%3D10%5E%7B-4%7D%3D1x10%5E%7B-4%7DM)
It means that:
![\frac{[H^+]_{pH=4}}{[H^+]_{pH=7}} =\frac{1x10^{-4}M}{1x10^{-7}M}\\ \\\frac{[H^+]_{pH=4}}{[H^+]_{pH=7}}=1000](https://tex.z-dn.net/?f=%5Cfrac%7B%5BH%5E%2B%5D_%7BpH%3D4%7D%7D%7B%5BH%5E%2B%5D_%7BpH%3D7%7D%7D%20%3D%5Cfrac%7B1x10%5E%7B-4%7DM%7D%7B1x10%5E%7B-7%7DM%7D%5C%5C%20%5C%5C%5Cfrac%7B%5BH%5E%2B%5D_%7BpH%3D4%7D%7D%7B%5BH%5E%2B%5D_%7BpH%3D7%7D%7D%3D1000)
It means that the concentration of hydrogen at a pH of 4 is 1000 times greater than the concentration of hydrogen at a pH of 7.
Regards.
The two main variables in an experiment are the independent and dependent variable.
An independent variable is the variable that is changed or controlled in a scientific experiment to test the effects on the dependent variable.
A dependent variable is the variable being tested and measured in a scientific experiment.
The dependent variable is 'dependent' on the independent variable. As the experimenter changes the independent variable, the effect on the dependent variable is observed and recorded.
For example, a scientist wants to see if the brightness of light has any effect on a moth being attracted to the light. The brightness of the light is controlled by the scientist. This would be the independent variable. How the moth reacts to the different light levels (distance to light source) would be the dependent variable.
When results are plotted in graphs, the convention is to use the independent variable as the x-axis and the dependent variable as the y-axis.
Nitrogen Cycle steps:
N molecules breaking apart via nitrogen-fixing bacteria.
Animals ingest nitrogen in nitrate-containing food after plants use nitrogen-containing compounds.
The organic matter decays via decomposers
N2 is formed via denitrifying bacteria.
Explanation:
The nitrogen-fixing bacteria removes atmospheric nitrogen by fixing nitrogen through nitrification. The atmospheric nitrogen cannot be absorbed by plants and hence has to be converted into nitrates. This conversion takes place by nitrifying bacteria present in leguminous plants.
Animals (herbivores) consume the plants that have absorbed nitrogen/
When these animals die, decomposing bacteria acts on the dead organic matter, decomposition takes place through ammonification, converting the organic nitrates into ammonia
The nitrates are converted back again to nitrogen by the action of denitrifying bacteria.
The nitrogen thus formed is released to the atmosphere
Answer:
Correct
Explanation:
Homeostatic is nothing but ability of a system or living organism to manipulate its internal environment to maintain a stable equilibrium, for example the ability of warm-blooded animals to ascertain a constant body temperature.
The Homoeostatic feedback mechanism has three basis components and they are independent to one another.
These components are receptor, effector and integrating center. The function of receptor is to sense external stimuli and send information to integrating center. The integrating center generally hypothalmus in brain sends this signal to effector for example an organ to react to the stimuli.
So, the order in a homeostatic feedback system stimulus, receoptor, control centre, effector is correct.
The correct answer is: A. The hydrophilic head groups of the lipid molecules are exposed to the outside of the cell and the cytoplasm, which is a water-like environment. The hydrophobic tails form an oily layer inside the membrane that keeps water out of the cell.
Plasma membrane of the cell is arranged in a bilayer of phospholipids. Phospholipids are amphipathic molecules which means that they have both hydrophilic and hydrophobic regions. The hydrophilic heads of phospholipids that are faced outward and hydrophobic layer located in the interior of the bilayer together make a good barrier between the interior and exterior of the cell, so the water and other polar or charged substances cannot easily cross the hydrophobic core of the membrane.
