Answer:
A- upfield
B- down field
C- splitting
D- chemical shift
E- integration
Explanation:
NMR is a spectroscopic technique commonly used to observe the magnetic fields around the nucleus of atoms in a compound under investigation.
A chemical shift is the difference in parts per million (ppm) between the resonance frequency of the observed protons in the compound under study and that of the tetramethylsilane (TMS) (the reference compound in NMR with a chemical shift of zero ppm because all protons in the compound are equivalent).
If signals appear close to the reference signal, the signals are said to appear upfield. If the signals appear far away from the reference, they are said to appear down field.
The presence of protons cause splitting of peaks to the magnitude of n+1. n is the number of neighboring protons. Splitting refers to the appearance of multiple peaks for a single nucleus due to neighboring nuclei.
The area of a signal that corresponds to the number of nuclei at that frequency is called the integration.
The final volume of the air in the balloon would be about 5.4 L
Answer:
B) PO2
Explanation:
first solve empirical formula
50%of P and 50%of O
- divide each by molecular mass
P. O
50/32. 50/16
1.5. 3.0
- divide both by the smallest
1.5/1.5. 3.0/1.5
1. :. 2
Empirical formula=PO2
Molecular formula=PO2
(PO2)n= 64
(32+(16×2)=64
(32+32)n=64
64n=64
n= 1
Answer:
The reactant/reagent that would be most atom economical is EtI (Ethy Iodide) and KOH (potassium oxide) as base
This is because the iodo group are weak base hence they have a good leaving character (i.e they are unstable on their own ) which would increase the rate of reaction and the strong base KOH give the most atom economical
Explanation:
Explanation:
Elements that belong to same group contains same number of valence electrons. Hence, they tend to show similar chemical properties.
When we move across a period then number of electrons get added to the same shell. As a result, there will be no increase in size of elements.
Also, metals are the elements that belong to group 1, 2 and d-block elements are also known as metals. Metallic character of elements decreases when we move left to right in a periodic table.
As most reactive metals are placed on the left side of periodic table.
Since, size of elements increases on moving down the group. So, an element is able to easily lose its valence electrons because of less force of attraction between its nucleus and valence electrons.
As a result, there will be increase in reactivity of metals on moving down the group.
Thus, we can conclude that given sentences are as follows.
- Elements in the same group have the same number of valence electrons.
-
Elements in the same period have the same number of electron shells.
-
Metallic elements become less reactive as you move left to right in a period.
-
Metallic elements become more reactive as you move top to bottom in a group.
