Chemistry 141 - MSUFORM A REAL EXAM|
LATEST EXAM WITH 100 QUESTIONS &
100% CORRECT DETAILED ANSWERS
(BRAND NEW!!)
Differentiate between heterogeneous and homogeneous mixtures - ANSWER//1.
Heterogeneous Mixture: composition varies from one region of the mixture to another.
They don't mix uniformly.
2. Homogeneous Mixture: have same composition throughout. They mix uniformly.
I know the SI base units for length, mass, time and temperature - ANSWER//Meter (m)
= Length
Kilogram (kg) = Mass
Second (s) = Time
Kelvin (K) = Temperature
Importance of reporting correct units with measurements - ANSWER//Without units, the
results are unclear and it is hard to keep track of what each separate measurement
entails. Units of measurement are the terms that we use to describe the size of
something. You probably know that units include things like seconds, kilograms, meters,
and so forth.
Without standard units of measurement, scientists would have a huge problem
understanding what other scientists were saying.
What unit system do scientists use? - ANSWER//The International System of Units (SI).
Law of Conservation of Mass and who created it - ANSWER//Antoine Lavoisier said "in
a chemical reaction, matter is neither created nor destroyed". The total mass of the
substances involved in the reaction does not change.
Radioactivity - ANSWER//The emission of elementary particles by some atoms when
their unstable nuclei disintegrate (see half-life). Materials composed of such atoms are
radioactive. (See alpha radiation, beta radiation, and gamma radiation.)
Nucleus - ANSWER//nucleus is the positively charged center of the atom consisting of
protons and neutrons.
Proton - ANSWER//A positively charged particle within a nucleus ... The number of
protons in an element's nucleus is called the atomic number.
Neutron - ANSWER//Neutral partials witching a nucleus. They contain no electrical
charge
subatomic particle found in the nucleus of atoms that differs from the other subatomic
particles (called "protons") in the nucleus of atoms because neutrons have no (zero)
,charge whereas each proton has a positive charge of +1.
Atomic Mass Unit - ANSWER//AMU - 1/12 of the mass of a carbon -12 atom
it is a unit of mass used to express atomic masses and molecular masses.
,Atomic Number - ANSWER//The number of protons in a atom's nucleus and is given the
symbol Z
Chemical Symbol - ANSWER//an abbreviation of a chemical element, symbols in a
periodic table
Isotope - ANSWER//An atom that has the same number of protons but different number
of neutrons
What is a mass number and the symbol represents it? - ANSWER//It is the sum of
neutrons and protons in an atom and is represented by the symbol A. It also can me
written as X-A. Ex: Ne-20
Natural Abundance - ANSWER//abundance of isotopes of a chemical element as
naturally found on a planet
when a natural element has a roughly constant percentage of isotopes
Ion - ANSWER//an atom that has obtained a charge - either + or -.
Anion - ANSWER//- a negatively charged ion
Cation - ANSWER//- a positively charged ion
Periodic Table - ANSWER//All elements are defined by a 1 or 2 letter symbol. The
atomic number listed on top tells us the number of protons and vice-versa
accuracy - ANSWER//the measure of how close a measurement is to the actual, exact
value
Precision - ANSWER//the relative proximity of a set of measurements to each other or
how reproducible they are. For an individual measurement - how many places to the
right of the decimal are reported.
Random error - ANSWER//Random error is always present in a measurement. It is
caused by inherently unpredictable fluctuations in the readings of a measurement
apparatus or in the experimenter's interpretation of the instrumental reading.
Systematic Error - ANSWER//. A systematic error (an estimate of which is known as a
measurement bias) is associated with the fact that a measured value contains an offset.
This type of error affects all of the data by shifting it either too high or low. This is an
error that is built into the apparatus and can not be reduced by repeat readings. To
remove the size of the error is found and then minused from all of the results.
Density - ANSWER//mass per unit volume of a substance
Relationship between mass and volume D=Mass/Volume
, Intensive Properties of Matter - ANSWER//a property that depends on the type of matter
in a sample, not the amount of matter. (Intensive Properties can be helpful clues to
identifying unknown substances.
a property that depends on the type of matter in a sample, not the amount of matter.
(Intensive Properties can be helpful clues to identifying unknown substances.
Extensive Properties of Matter - ANSWER//property that depends on the amount of
matter in a sample
Extensive properties, such as mass and volume, depend on the amount of matter that
is being measured.
Energy - ANSWER//The ability to do work or produce heat.
Kinetic Energy - ANSWER//Energy due to the motion of the object.
Potential Energy - ANSWER//Energy due to position or composition.
Thermal Energy - ANSWER//Thermal energy is the internal energy of an object due to
the kinetic energy of its atoms and/or molecules. The atoms and/or molecules of a
hotter object have greater kinetic energy than those of a colder one, in the form of
vibrational, rotational, or, in the case of a gas, translational motion.
Law of Conservation of Energy - ANSWER//Energy can be converted from one form to
another but can neither be created nor destroyed.
and total energy remains constant
Mole - ANSWER//The amount of a substance that contains 6.02 x 10^23 representative
particles of that substance
The unit of a mole gives us a way of counting a large number of items with smaller
numbers
Avogadro's number - ANSWER//-the number of representative particles contained in
one mole of a substance; equal to 6.02 x 10^23 particles.
- Avogadro's number is a proportion that relates molar mass on an atomic scale to
physical mass on a human scale. Avogadro's number is defined as the number of
elementary particles (molecules, atoms, compounds, etc.) per mole of a substance. It is
equal to 6.022×1023 mol-1 and is expressed as the symbol NA.
amplitude - ANSWER//related to the vertical height of the crest and determines the
intensity of the light
wavelength - ANSWER//is the physical distance between crests of the light wave
frequency - ANSWER//the number of crests that pass a point in a given time
LATEST EXAM WITH 100 QUESTIONS &
100% CORRECT DETAILED ANSWERS
(BRAND NEW!!)
Differentiate between heterogeneous and homogeneous mixtures - ANSWER//1.
Heterogeneous Mixture: composition varies from one region of the mixture to another.
They don't mix uniformly.
2. Homogeneous Mixture: have same composition throughout. They mix uniformly.
I know the SI base units for length, mass, time and temperature - ANSWER//Meter (m)
= Length
Kilogram (kg) = Mass
Second (s) = Time
Kelvin (K) = Temperature
Importance of reporting correct units with measurements - ANSWER//Without units, the
results are unclear and it is hard to keep track of what each separate measurement
entails. Units of measurement are the terms that we use to describe the size of
something. You probably know that units include things like seconds, kilograms, meters,
and so forth.
Without standard units of measurement, scientists would have a huge problem
understanding what other scientists were saying.
What unit system do scientists use? - ANSWER//The International System of Units (SI).
Law of Conservation of Mass and who created it - ANSWER//Antoine Lavoisier said "in
a chemical reaction, matter is neither created nor destroyed". The total mass of the
substances involved in the reaction does not change.
Radioactivity - ANSWER//The emission of elementary particles by some atoms when
their unstable nuclei disintegrate (see half-life). Materials composed of such atoms are
radioactive. (See alpha radiation, beta radiation, and gamma radiation.)
Nucleus - ANSWER//nucleus is the positively charged center of the atom consisting of
protons and neutrons.
Proton - ANSWER//A positively charged particle within a nucleus ... The number of
protons in an element's nucleus is called the atomic number.
Neutron - ANSWER//Neutral partials witching a nucleus. They contain no electrical
charge
subatomic particle found in the nucleus of atoms that differs from the other subatomic
particles (called "protons") in the nucleus of atoms because neutrons have no (zero)
,charge whereas each proton has a positive charge of +1.
Atomic Mass Unit - ANSWER//AMU - 1/12 of the mass of a carbon -12 atom
it is a unit of mass used to express atomic masses and molecular masses.
,Atomic Number - ANSWER//The number of protons in a atom's nucleus and is given the
symbol Z
Chemical Symbol - ANSWER//an abbreviation of a chemical element, symbols in a
periodic table
Isotope - ANSWER//An atom that has the same number of protons but different number
of neutrons
What is a mass number and the symbol represents it? - ANSWER//It is the sum of
neutrons and protons in an atom and is represented by the symbol A. It also can me
written as X-A. Ex: Ne-20
Natural Abundance - ANSWER//abundance of isotopes of a chemical element as
naturally found on a planet
when a natural element has a roughly constant percentage of isotopes
Ion - ANSWER//an atom that has obtained a charge - either + or -.
Anion - ANSWER//- a negatively charged ion
Cation - ANSWER//- a positively charged ion
Periodic Table - ANSWER//All elements are defined by a 1 or 2 letter symbol. The
atomic number listed on top tells us the number of protons and vice-versa
accuracy - ANSWER//the measure of how close a measurement is to the actual, exact
value
Precision - ANSWER//the relative proximity of a set of measurements to each other or
how reproducible they are. For an individual measurement - how many places to the
right of the decimal are reported.
Random error - ANSWER//Random error is always present in a measurement. It is
caused by inherently unpredictable fluctuations in the readings of a measurement
apparatus or in the experimenter's interpretation of the instrumental reading.
Systematic Error - ANSWER//. A systematic error (an estimate of which is known as a
measurement bias) is associated with the fact that a measured value contains an offset.
This type of error affects all of the data by shifting it either too high or low. This is an
error that is built into the apparatus and can not be reduced by repeat readings. To
remove the size of the error is found and then minused from all of the results.
Density - ANSWER//mass per unit volume of a substance
Relationship between mass and volume D=Mass/Volume
, Intensive Properties of Matter - ANSWER//a property that depends on the type of matter
in a sample, not the amount of matter. (Intensive Properties can be helpful clues to
identifying unknown substances.
a property that depends on the type of matter in a sample, not the amount of matter.
(Intensive Properties can be helpful clues to identifying unknown substances.
Extensive Properties of Matter - ANSWER//property that depends on the amount of
matter in a sample
Extensive properties, such as mass and volume, depend on the amount of matter that
is being measured.
Energy - ANSWER//The ability to do work or produce heat.
Kinetic Energy - ANSWER//Energy due to the motion of the object.
Potential Energy - ANSWER//Energy due to position or composition.
Thermal Energy - ANSWER//Thermal energy is the internal energy of an object due to
the kinetic energy of its atoms and/or molecules. The atoms and/or molecules of a
hotter object have greater kinetic energy than those of a colder one, in the form of
vibrational, rotational, or, in the case of a gas, translational motion.
Law of Conservation of Energy - ANSWER//Energy can be converted from one form to
another but can neither be created nor destroyed.
and total energy remains constant
Mole - ANSWER//The amount of a substance that contains 6.02 x 10^23 representative
particles of that substance
The unit of a mole gives us a way of counting a large number of items with smaller
numbers
Avogadro's number - ANSWER//-the number of representative particles contained in
one mole of a substance; equal to 6.02 x 10^23 particles.
- Avogadro's number is a proportion that relates molar mass on an atomic scale to
physical mass on a human scale. Avogadro's number is defined as the number of
elementary particles (molecules, atoms, compounds, etc.) per mole of a substance. It is
equal to 6.022×1023 mol-1 and is expressed as the symbol NA.
amplitude - ANSWER//related to the vertical height of the crest and determines the
intensity of the light
wavelength - ANSWER//is the physical distance between crests of the light wave
frequency - ANSWER//the number of crests that pass a point in a given time
