Answer: The correct option is The properties of a noble gas.
Explanation: There are 7 periods in the periodic table.
The last element of each period are Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), Radon (Rn) and Ununoctium (Uuo).
- The electronic configuration for Helium is
. For He, The outermost electrons are 2.
- The electronic configuration for all the other elements is
( where, n = 2, 3, 4, 5, 6 and 7 respectively). For all the other gases, the outermost electrons are 8.
All these elements have stable electronic configuration and are not reactive in nature. Hence, they are considered as noble gases.
Therefore, the last element of each period always have the properties of a noble gas.
Answer:
In the twentieth century, criminologists and forensics strive to summarize the preceding discoveries. In different countries tendencies are beginning to manifest that increase the field of criminological activity in different branches such as criminalistics in Germany; others, penology; and others like the United States, weighed the study as a whole of the science of crime and the science of social reaction provoked by it. In this century, criminology and forensic science had a notable influence on the evolution of criminal law.
Starting in the mid-20th century, a paradigm shift in forensic criminological science was presented, focusing on the study of three aspects: criminal processes, the social environment, and the victim.
Other factors that were taken into account were biosecurity care, which began to have great relevance and greater care since they began to discover infectious diseases transmitted by cadavers to humans.
Approximately in 1939 it was discovered that anthropometric measurements are values that present similarities between different skeleton patterns.
Explanation:
Legal dentistry also addresses the aspect related to “professions” and people's habits, for example, by 1925 it was already possible to identify a smoker by the coloration that the teeth took and the wear on the incisors and canines where the cigar rested. The morphological characteristics of the teeth were, in many cases, used to identify those they called "degenerates", who were the ones who went outside the guidelines of psychic "normality" of the time; among these were prostitutes, thieves, who according to the author had a considerable volume in the molars, the canines were triangular and long, like the upper central incisors that in some reached 8 mm.
<h3><u>Full Question:</u></h3>
The following compound has been found effective in treating pain and inflammation (J. Med. Chem. 2007, 4222). Which sequence correctly ranks each carbonyl group in order of increasing reactivity toward nucleophilic addition?
A) 1 < 2 < 3
B) 2 < 3 < 1
C) 3 < 1 < 2
D) 1 < 3 < 2
<h3><u>Answer: </u></h3>
The rate of nucleophilic attack of carbonyl compounds is 2<3 <1.
Option B
<h3><u>Explanation. </u></h3>
Nucleophilic attack is explained as the attack of an electron rich radical to a carbonyl compound like aldehyde or a ketone. A nucleophile has a high electron density, so it searches for a electropositive atom where it can donate a portion of its electron density and become stable.
A carbonyl compound is a 
hybridized carbon atom with a double bonded oxygen atom in it. The oxygen atom pulls a huge portion of electron density from carbon being very electropositive.
In a ketone, there are two factors that make it less likely to undergo a nucleophilic attack than aldehyde. Firstly, the steric hindrance of two carbon groups being attached with the carbonyl carbon makes it harder for the nucleophile to approach. Secondly, the electron push by the carbon groups attached makes the carbonyl carbon a bit less electropositive than the aldehyde one. So aldehydes are more reactive towards a nucleophilic addition reaction.
The answer is B. the molar mass.
The molar mass of a chemical compound is defined as the mass of a sample of that compound divided by the amount of substance in that sample, measured in moles.
Molecules move from areas of high concentration to areas of low concentration.
