Answers – Organic Chemistry, Reactions,
Functional Groups
Description:
This chemistry-focused HPAT exam guide provides practice questions with correct
answers on organic chemistry, functional groups, chemical bonding, and reaction
types. It covers alkanes, alkenes, alkynes, covalent bonds, isotopes, and acids.
Essential for candidates who need detailed chemistry practice for HPAT.
double-displacement reaction - answer✔✔A double displacement reaction, also
known as a double replacement reaction or metathesis, is a type of chemical reaction
where two compounds react, and the positive ions (cation) and the negative ions
(anion) of the two reactants switch places, forming two new compounds or products
Precipitate - answer✔✔precipitate is an insoluble solid that emerges from a liquid
solution. The emergence of the insoluble solid from solution is called precipitation.
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Often the precipitate emerges as a suspension. Precipitates can form when two
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, soluble salts react in solution to form one or more insoluble products. Energy Levels -
answer✔✔Energy levels (also called electron shells) are fixed distances from the
nucleus of an atom where electrons may be found. As you go farther from the
nucleus, electrons at higher energy levels have more energy. Electrons in the
outermost energy level of an atom are called valence electrons Marquis Test -
answer✔✔The Marquis Test is commonly used for Ecstasy testing as MDMA turns
the precipitate purple black. Cobalt thiocyanate is used to test for cocaine. The
Cobalt is mixed with the questionable substance, then drowned in hydrochloric acid,
doused in chloroform, and shaken. What is the relation between an atomic number
and a mass number? - answer✔✔Atomic number is actually the number of
protons in an atom while mass number is the number of nucleons i. e, number of
protons plus the number of neutrons. Isotopes - answer✔✔Isotopes refer to the
nuclides of a certain element that have different numbers of neutrons, or in other
words, atomic nuclei that have the same number of protons but different numbers of
neutrons. A radioisotope is an isotope that is unstable and therefore undergoes
radioactive decay or will at some point. Chemical Synthesis - answer✔✔Chemical
synthesis, the construction of complex chemical compounds from simpler ones. It is
the process by which many substances important to daily life are obtained. It is
applied to all types of chemical compounds, but most syntheses are of organic
molecules. Decomposition - answer✔✔A decomposition reaction is a type of
chemical reaction in which a single compound breaks down into two or more
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