<span>C4H4
The compound in question has an equal ratio of hydrogen and carbon. The atomic weight of carbon is roughly 12 and the atomic weight of hydrogen is roughly 1. The mass of the compound in question is roughly 52.
52/13=4
C4H4</span>
<span>pharmacokinetics
This question is simply a matter of knowing the definition of terms being used in your class. So let's look at the 4 options and see what makes sense.
spectrometry
* This is the determination of elements based upon the light spectrum associated with the elements. It can be either an emission spectrum you get by energizing the substance under test, or an absorption spectrum to see what wavelengths the substance absorbs. But in either case, this doesn't make sense in the statement, so it's a wrong answer.
LD50
* This terms means "Lethal Dose 50%" which is the amount of the substance needed such that half of the creatures that receive that dose die. In the context of the statement, this doesn't make sense, so it's a wrong answer.
pharmacokinetics
* This is the study of how drugs move through the body and are metabolized. This sounds like something that makes sense for the statement in the question, so it's most likely the correct answer. Let's see what the next choice is.
chromatography
* This is a laboratory method of separating substances using differential rates of diffusion. This doesn't make sense given the statement in the question, so it's a wrong choice.
So of the 4 available choices, 3 of them do not make sense given the statement in question and the only one that does make sense is "pharmacokinetics"</span>
Li2O is the formula for <span> lithium oxide</span>
Answer: 1.32
Explanation:
First, we must obtain the molar mass of HBr. After that, we try to obtain the concentration of the hydrobromic acid from the formula n=CV since the volume of solution and mass of acid was provided. Recall that n=m/M. If the concentration of acid is thus obtained, we make use of the fact that the concentration of H+ in the acid is equal to the molar concentration of HBr to obtain the pH. The pH is the negative logarithm of the concentration we obtained in the initial step.
As can be seen in the attached image, α-pyrone has a highly electrophilic carbon atom, since it is attached to two oxygen atoms that are electronegative and subtract electrical charge from the carbon, leaving it with a <u>positive partial charge</u>. By virtue of the above, <u>the bromine atoms, which have an important electron density that makes them good nucleophiles, will be attracted to the aforementioned carbon due to their positive charge</u>, thus favoring the substitution product to a greater extent than that of addition.
