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SVETLANKA909090 [29]
1 year ago
13

Why is it necessary to heat the samples prior to collection of the headspace samples?

Social Studies
1 answer:
irina [24]1 year ago
8 0

To drive partitioning of volatiles from the solid or liquid phase into the gas phase

Usually, heat is applied to the headspace vials to encourage the partitioning of volatiles from the solid or liquid phase into the gas phase. During heating, sample vials may be shaken. A heated gas-tight syringe is typically used to sample the headspace prior to GC/MS injection.

In order to raise the sample vapour pressure and acquire a more favourable distribution constant, headspace sampling is frequently carried out at high temperatures. Due to the potential for the sample container to rupture, this approach has restricted experimental use. It is important to take into account the sample's thermal stability.

Learn more about headspace here:

brainly.com/question/4324701

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What is biology? what key question does biology seek to answer? what is the key idea of christian biology?
kolezko [41]
Biology is a branch of science that studies about life and living organisms. It includes physical and chemical structure, development, and evolution of all living things. It seeks to answer questions about all living things.A biologist may ask about how plants maintain life processes. In Christian biology, biblical knowledge and faith are integrated in learning the evolution of the earth and the living things that consist it. Likewise, it states that God's signature is written in his creation or the living world is a testament of God's actions.
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3 years ago
Read 2 more answers
1. Over time the economy of Europe changed from one based solely on agriculture to one focused more on trading and the merchant
Slav-nsk [51]

1.    Over time the economy of Europe changed from one based solely on agriculture to one focused more on trading and the merchant class, why did this transition take place?

Around 3000 BC, influenced by the culture of the Middle East, emerged the first European culture, the Greeks, who structured around the so-called polis (autonomous communities) before this, predominated nomadic tribes, who based their survival in hunting and gathering. The foundation of the first cities (human conglomerates, where mutually it was contributed for social welfare). During this time, Europe was immersed in multiple wars, territorial issues until Alexander the Great undertook the conquest of the eastern world and this model prevailed after his death (323 a.C.)  

The Eastern powers returned to be independent, Macedonia remained like the high power, and therefore it became the great merchant, which transformed notably the interchange of goods and riches, in all the continent and its relation with North Africa and Asia.

2. How did Europe transition from a system of feudalism to one organized into nation-states?

From at least 250 a.C. and until 235, the Roman Empire prevailed, colonizing a large part of Europe, imposing its model of government and economy. In 313, Constantine decreed religious tolerance towards Christians in the so-called "Edict of Milan," while in 395, Theodosius the Great proclaimed Christianity as the official religion of the Empire. In this period, and particularly since the Council of Nicea onwards, Christianity developed strong hierarchical structures, in addition to actively developing doctrine and dogmas of faith. In that sense, Christianity began to create the appearance that the Catholic Church would present during the Middle Ages, and with the beginning of the Middle Ages, the fiefs created over the Roman colonies, took place as the city model, where the command of the feudal lord, the peasants and merchants received protection behind the walls of the cities, in exchange for security and payment of taxes. This model prevailed for centuries throughout Europe. It is generally considered that the empire ended after the fall of Constantinople under the Ottoman Turks in 1453.

The first signs of the renaissance of civilization in Western Europe began to appear in the 11th century, when trade began again in Italy, giving rise to the economic situation and cultural growth of independent city-states, such as Venice and Florence. At the same time, the nation-states began to take shape in places like France, England, Spain, and Portugal, although the process of their formation (usually marked by the rivalry between the monarchy, the aristocracy feudal lords and the church) it lasted several centuries. These new nation-states began to write in their languages instead of traditional Latin. On the other hand, the Holy Roman Empire, based essentially on Germany and Italy, was fragmented into countless feudal principalities or small city-states, whose subordination to the emperor was only formal.

3.    How did the Catholic Church react to those who disagreed to their teaching and practices during the middle ages?

After the Great Schism of East and West, western Christianity approved by the newly created kingdoms of Central Europe: Poland, Hungary, and Bohemia. The Catholic Church developed as a great power, giving rise to conflicts between the pope and the Emperor. In 1129 the Catholic Church established the Inquisition to make Western Europeans its members by force. The Inquisition punished those who practice heresy to repent. If they did not, they suffered the death penalty. During this time many nobles ruled the church. The monks of Cluny managed to establish a church where the nobles did not exist. Pope Gregory VII, continued the work of the monks with two main objectives: rid the church of the control of the kings and nobles and increase the power of the pope. The influence of the Catholic Church had grown enormously due to the conversions of pagan kings (Scandinavia, Poland, Hungary, Lithuania), Christian Reconquest of Al-Andalus, and the Crusades. As a result, most of Europe was Catholic in the fifteenth century.


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3 years ago
Sociologists refer to the process of maintaining or changing behavior to comply with the norms established by a society, subcult
vova2212 [387]

Answer:

conformity

Explanation:

<h2><u>Fill in the blanks</u></h2>

Sociologists refer to the process of maintaining or changing behavior to comply with the norms established by a society, subculture, or other group as <u>conformity </u>

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Help! I’ll give points
Svet_ta [14]

Explanation:

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Which term refers to whether a value is seen as positive or negative?
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The answer is A. Valence
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