AC HPAT EXAMPREP REVIEW SHEET WITH
TESTED QUESTIONS AND COMPLETE
SOLUTIONS
●● Precipitate
Answer: precipitate is an insoluble solid that emerges from a liquid
solution. The emergence of the insoluble solid from solution is called
precipitation. Often the precipitate emerges as a suspension. Precipitates
can form when two 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 elements or
new compounds. These reactions often involve an energy source such as
heat, light, or electricity that breaks apart the bonds of compounds
●● single-displacement reaction
, Answer: A single-displacement reaction, also known as a single-
replacement reaction, is a type of chemical reaction where an element
reacts with a compound and takes the place of another element in that
compound. This type of reaction is typically pictured like this: Here, A
replaces B in the compound BC
●● Flame test
Answer: flame test is an analytical procedure used in chemistry to detect
the presence of certain elements, primarily metal ions, based on each
element's characteristic emission spectrum. The color of flames in
general also depends on temperature; see flame color.
●● Precipitation reaction
Answer: A precipitation reaction refers to the formation of an insoluble
salt when two solutions containing soluble salts are combined. The
insoluble salt that falls out of solution is known as the precipitate, hence
the reaction's name. Precipitation reactions can help determine the
presence of various ions in solution.
●● organic compounds
Answer: An organic compound is a substance that is added to a product,
like food, to improve some qualities such as taste, smell, colour and
texture. These substances can be both positive and negative for human
health.
●● Synthetic materials
TESTED QUESTIONS AND COMPLETE
SOLUTIONS
●● Precipitate
Answer: precipitate is an insoluble solid that emerges from a liquid
solution. The emergence of the insoluble solid from solution is called
precipitation. Often the precipitate emerges as a suspension. Precipitates
can form when two 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 elements or
new compounds. These reactions often involve an energy source such as
heat, light, or electricity that breaks apart the bonds of compounds
●● single-displacement reaction
, Answer: A single-displacement reaction, also known as a single-
replacement reaction, is a type of chemical reaction where an element
reacts with a compound and takes the place of another element in that
compound. This type of reaction is typically pictured like this: Here, A
replaces B in the compound BC
●● Flame test
Answer: flame test is an analytical procedure used in chemistry to detect
the presence of certain elements, primarily metal ions, based on each
element's characteristic emission spectrum. The color of flames in
general also depends on temperature; see flame color.
●● Precipitation reaction
Answer: A precipitation reaction refers to the formation of an insoluble
salt when two solutions containing soluble salts are combined. The
insoluble salt that falls out of solution is known as the precipitate, hence
the reaction's name. Precipitation reactions can help determine the
presence of various ions in solution.
●● organic compounds
Answer: An organic compound is a substance that is added to a product,
like food, to improve some qualities such as taste, smell, colour and
texture. These substances can be both positive and negative for human
health.
●● Synthetic materials
