One way is for <span>a landowner to gather as much information as possible about his or her private water well, to know how it works, as well as who has had the land before them. The landowner needs to see if anyone has used pesticides in the area, as it can contaminate the well water. This is the most common way. The landowner can also check to see if any other chemicals have been spilt in the area or even a gas or oil leak, as that too can cause the contamination of well water.
I hope this helps.</span>
Answer:
8.09x10⁻⁵M of Fe³⁺
Explanation:
Using Lambert-Beer law, the absorbance of a sample is proportional to its concentration.
In the problem, the Fe³⁺ is reacting with KSCN to produce Fe(SCN)₃ -The red complex-
The concentration of Fe³⁺ in the reference sample is:
4.80x10⁻⁴M Fe³⁺ × (5.0mL / 50.0mL) = 4.80x10⁻⁵M Fe³⁺
<em>Because reference sample was diluted from 5.0mL to 50.0mL.</em>
<em>That means a solution of 4.80x10⁻⁵M Fe³⁺ gives an absorbance of 0.512</em>
Now, as the sample of the lake gives an absorbance of 0.345, its concentration is:
0.345 × (4.80x10⁻⁵M Fe³⁺ / 0.512) = <em>3.23x10⁻⁵M. </em>
As the solution was diluted from 20.0mL to 50.0mL, the concentration of Fe³⁺ in Jordan lake is:
3.23x10⁻⁵M Fe³⁺ × (50.0mL / 20.0mL) = <em>8.09x10⁻⁵M of Fe³⁺</em>
<span>Cetylphyridinium chloride is commonly used to clean teeth, as used in many mouthwashes and toothpastes. </span>
According to Dalton, every atom in an element has the same mass, and compounds are made up of a particular ratio of several elements. Thus the mass percentages of K, N, and O in potassium nitrate from India and Italy are the same.
The laws of conservation of mass and constant composition served as the foundation for Dalton's theory. In the first section of his thesis, he claims that all matter is composed of indivisible atoms. According to the second component of the theory, the mass and characteristics of every atom in a specific element are the same. Parts of the theory had to be modified based on the existence of subatomic particles and isotopes.
Learn more about Dalton's theory here:
brainly.com/question/1403872
#SPJ4
Answer: It informs the audience if the study included controlled tests.
Explanation: Usually, scientific conferences involve presentation of papers by scientists. These paper presentations are actually the sharing of details of the scientific research carried out by other scientists.
Presenting the materials and methods section of the a research project to a scientific conference informs the audience if the study included controlled tests.
The inclusion of controlled tests in a scientific study enhances the validity of the results obtained in the study.