Seas are smaller than oceans. Oceans are where land and water meet, and are usually bigger.
Answer:
Field experiments can often have the potential to give scientists opportunities that are not possible in a lab setting.
Explanation:
Having people "act natural" in a lab setting is impossible to truly achieve, as we all know what happens to our mental state and behavior when we are being actively observed. This is also especially helpful when conducting wildlife research, as there are a myriad of different things influencing animal and plant behavior that would be nigh impossible to recreate perfectly in a controlled lab setting.
Field research can have its disadvantages as well, as it is very hard to only have one thing change (make an independent variable) in a wild environment with ever-changing weather, social effects, etc. Also, you, as the researcher, as causing an impact on the very location that you are observing, which can alter your results in unpredictable ways.
The thing to remember is that each type of study has its advantages and disadvantages; if they didn't, then we'd all do the same type of research! You have to weigh your research options and figure out which one works best for your situation :)
Answer:
The correct answer is: pH= 4.70
Explanation:
We use the <em>Henderson-Hasselbach equation</em> in order to calculate the pH of a buffer solution:
![pH= pKa + log \frac{ [conjugate base]}{[acid]}](https://tex.z-dn.net/?f=pH%3D%20pKa%20%2B%20log%20%20%20%5Cfrac%7B%20%5Bconjugate%20base%5D%7D%7B%5Bacid%5D%7D)
Given:
pKa= 4.90
[conjugate base]= 4.75 mol
[acid]= 7.50 mol
We calculate pH as follows:
pH = 4.90 + log (4.75 mol/7.50 mol) = 4.90 + (-0.20) = 4.70
Answer:-
Oxygen gains electrons and is reduced.
Explanation:-
For this reaction the balanced chemical equation is
4Fe + 3O2 --> 2Fe2O3
When Oxygen is present as oxygen gas, the oxidation number of O is Zero since it is the only element present in Oxygen gas.
Similarly Iron is present in Fe with oxidation number Zero.
In the case of Fe2O3, Oxygen has the oxidation number -2 while Iron has +3.
So the oxidation number of Oxygen goes from Zero to -2.
Since the oxidation number decreases Oxygen is reduced.
Since reduction involves gain of electrons, Oxygen gains electrons.
This assumption is not valid because, there are some elements which exist in two or more forms; they have the same atomic number but differ in their mass number, which meas that they possess different number of neutrons. These type of element are called isotopes. Isotope have the same atomic number and similar physical and chemical properties but they have different number of neutrons and therefore possess different masses.