CHEM 1211 EXAM QUESTIONS ANSWERED CORRECTLY LATEST UPDATE 2026
chemistry - Answers the study of matter and the changes it undergoes
scientific method - Answers cycle of making observations, formulating hypotheses, and performing
experiments.
theory - Answers set of hypotheses that agree with observations. attempts to explain why
observations exist. nothing exactly proven
laws - Answers summarize past observations and predicts future ones. seen to be true consistently.
only states what will happen, not why.
matter - Answers anything that occupies space and has mass
three states of matter - Answers solid, liquid, and gas
solid - Answers fixed volume and shape, non-compressible.
liquid - Answers fixed volume but no fixed shape, non-compressible
gas - Answers no fixed volume or shape, compressible.
mass - Answers amount of matter in an object
weight - Answers amount of force gravity pulls on an object
pure substances - Answers matter that is composed of exactly one type of particle
element - Answers particle that is exactly one atom.
diatomic elements. - Answers elements that exist as pairs in nature. BrINClHOF
compounds - Answers particle has multiple types of atoms
mixture - Answers any substance that contains more than one type of particle. (not a pure substance)
homogenous mixture - Answers macroscopically uniform substance
heterogenous mixture - Answers macroscopically distinct substance
physical change - Answers changing how the substance looks macroscopically without changing the
chemical makeup of a substance
physical or chemical change: melting ice - Answers physical change
physical or chemical change: crumpling paper - Answers physical change
physical or chemical change: filtering - Answers physical change
physical or chemical change: rusting - Answers chemical
physical or chemical change: combustion - Answers chemical
chemical change - Answers changing the actual composition of the substance; making/breaking
chemical bonds.
physical or chemical change: sugar dissolving in water - Answers physical
physical or chemical change: cooking - Answers chemical
physical or chemical change: forging iron - Answers physical
physical or chemical change: fermenting yeast - Answers chemical
physical or chemical change: distillation - Answers physical
filtration - Answers separation based on size, density, state, etc.
distillation - Answers separating substances with different boiling points by heating them up until
only one of them boils.
chromatography - Answers separate non-solid substances by letting them stick to and move through
a solid surface.
quantitative measurements - Answers specific numerical values. often includes units.
qualitative measurements - Answers descriptive observations.
accuracy - Answers how close a measurement is to the actual value.
precision - Answers how close a measurement is to each other
unit for measuring length - Answers meter (m)
unit for measuring mass - Answers kilogram (kg)
unit for measuring time - Answers seconds (s)
unit for measuring amount - Answers mole (mol)
unit for measuring temperature - Answers kelvin (K)
unit for measuring electric current - Answers ampere (amp)
unit for measuring luminous intensity - Answers candella (cd)
scientific notation for "exa" - Answers 10^18
scientific notation for "peta" - Answers 10^15
scientific notation for "tera" - Answers 10^12
scientific notation for "giga" - Answers 10^9
, scientific notation for "mega" - Answers 10^6
scientific notation for "kilo" - Answers 10^3
scientific notation for "hecto" - Answers 10^2
scientific notation for "deka" - Answers 10^1
scientific notation for "deci" - Answers 10^-1
scientific notation for "centi" - Answers 10^-2
scientific notation for "milli" - Answers 10^-3
scientific notation for "micro" - Answers 10^-6
scientific notation for "nano" - Answers 10^-9
scientific notation for "pico" - Answers 10^-12
scientific notation for "femto" - Answers 10^-15
scientific notation for "atto" - Answers 10^-18
random errors - Answers errors both high and low, but will average out with more measurements.
systematic errors - Answers errors in only one directions. won't average out.
significant figures - Answers the number of digits that should be present in a result. keep certain
digits, plus one more.
counting sig fig rules. - Answers 1. all nonzero integers are significant figures.
2. leading zeros are not significant.
3. middle zeros are significant.
4. trailing zeros are significant only if there is a decimal.
5. exact numbers have infinite sig figs.
Sig figs with addition and subtraction - Answers result must have the same number of decimals as the
number with the least amount of decimals
sig figs with multiplication and division - Answers result must have the same number of sig figs as the
number with the least number of sig figs in the calculation
sig figs with logarithms - Answers result will have the same number of decimals as there are sig figs in
the logarithm.
Density - Answers mass/volume
intensive property - Answers do not depend on the amount of substance present
extensive property - Answers do depend on the amount of substance present
how many cm are in one inch? - Answers 2.54
law of conservation of mass - Answers mass is neither created nor destroyed in a chemical reaction
who developed the law of conservation of mass - Answers Lavoisier
law of definite proportions - Answers a given compound always contains exactly the same proportion
of elements by mass
who founded the law of definite proportions? - Answers Joseph Proust
Law of Multiple Proportions - Answers whenever two elements form more than one compound, the
different masses of one element that combine with the same mass of the other element are in the
ratio of small whole numbers
daltons atomic theory - Answers 1) elements are composed of atoms. 2) atoms of same element are
identical, but differ from other elements. 3) chemical compounds form when elements combine 4)
chemical reactions reorganize atoms, but the atoms don't change themselves.
JJ Thomson's cathode ray tube experiment - Answers - Around 1900, JJ Thomson used a cathode ray
tube to produce particles that we now call electrons.
- Took particles and shot it though two electric plates. Repelled by the negative field, so electrons
must be negatively charged.
- Used a magnetic field to determine the charge to mass ratio: -1.76e10 8 C/g
- Because these electrons could be produced from all metals, he concluded that every element must
contain electrons.
- If atom is neutral, then there must be some positively charged particle -> Plum Pudding Model.
Millikans Oil Drop Experiment: - Answers Millikans Oil Drop Experiment:
- Sprayed Oil on two electron plates. Charge of the electrons: -1.60e-19 C
- Using this new charge and the charge to mass ratio found by Thomson, he found the mass of the
electron: 9.11e-31 kg
Rutherford's Gold Foil Experiment: - Answers Rutherford's Gold Foil Experiment:
- Wanted to test the validity of Thomson's Plum Pudding Model.
chemistry - Answers the study of matter and the changes it undergoes
scientific method - Answers cycle of making observations, formulating hypotheses, and performing
experiments.
theory - Answers set of hypotheses that agree with observations. attempts to explain why
observations exist. nothing exactly proven
laws - Answers summarize past observations and predicts future ones. seen to be true consistently.
only states what will happen, not why.
matter - Answers anything that occupies space and has mass
three states of matter - Answers solid, liquid, and gas
solid - Answers fixed volume and shape, non-compressible.
liquid - Answers fixed volume but no fixed shape, non-compressible
gas - Answers no fixed volume or shape, compressible.
mass - Answers amount of matter in an object
weight - Answers amount of force gravity pulls on an object
pure substances - Answers matter that is composed of exactly one type of particle
element - Answers particle that is exactly one atom.
diatomic elements. - Answers elements that exist as pairs in nature. BrINClHOF
compounds - Answers particle has multiple types of atoms
mixture - Answers any substance that contains more than one type of particle. (not a pure substance)
homogenous mixture - Answers macroscopically uniform substance
heterogenous mixture - Answers macroscopically distinct substance
physical change - Answers changing how the substance looks macroscopically without changing the
chemical makeup of a substance
physical or chemical change: melting ice - Answers physical change
physical or chemical change: crumpling paper - Answers physical change
physical or chemical change: filtering - Answers physical change
physical or chemical change: rusting - Answers chemical
physical or chemical change: combustion - Answers chemical
chemical change - Answers changing the actual composition of the substance; making/breaking
chemical bonds.
physical or chemical change: sugar dissolving in water - Answers physical
physical or chemical change: cooking - Answers chemical
physical or chemical change: forging iron - Answers physical
physical or chemical change: fermenting yeast - Answers chemical
physical or chemical change: distillation - Answers physical
filtration - Answers separation based on size, density, state, etc.
distillation - Answers separating substances with different boiling points by heating them up until
only one of them boils.
chromatography - Answers separate non-solid substances by letting them stick to and move through
a solid surface.
quantitative measurements - Answers specific numerical values. often includes units.
qualitative measurements - Answers descriptive observations.
accuracy - Answers how close a measurement is to the actual value.
precision - Answers how close a measurement is to each other
unit for measuring length - Answers meter (m)
unit for measuring mass - Answers kilogram (kg)
unit for measuring time - Answers seconds (s)
unit for measuring amount - Answers mole (mol)
unit for measuring temperature - Answers kelvin (K)
unit for measuring electric current - Answers ampere (amp)
unit for measuring luminous intensity - Answers candella (cd)
scientific notation for "exa" - Answers 10^18
scientific notation for "peta" - Answers 10^15
scientific notation for "tera" - Answers 10^12
scientific notation for "giga" - Answers 10^9
, scientific notation for "mega" - Answers 10^6
scientific notation for "kilo" - Answers 10^3
scientific notation for "hecto" - Answers 10^2
scientific notation for "deka" - Answers 10^1
scientific notation for "deci" - Answers 10^-1
scientific notation for "centi" - Answers 10^-2
scientific notation for "milli" - Answers 10^-3
scientific notation for "micro" - Answers 10^-6
scientific notation for "nano" - Answers 10^-9
scientific notation for "pico" - Answers 10^-12
scientific notation for "femto" - Answers 10^-15
scientific notation for "atto" - Answers 10^-18
random errors - Answers errors both high and low, but will average out with more measurements.
systematic errors - Answers errors in only one directions. won't average out.
significant figures - Answers the number of digits that should be present in a result. keep certain
digits, plus one more.
counting sig fig rules. - Answers 1. all nonzero integers are significant figures.
2. leading zeros are not significant.
3. middle zeros are significant.
4. trailing zeros are significant only if there is a decimal.
5. exact numbers have infinite sig figs.
Sig figs with addition and subtraction - Answers result must have the same number of decimals as the
number with the least amount of decimals
sig figs with multiplication and division - Answers result must have the same number of sig figs as the
number with the least number of sig figs in the calculation
sig figs with logarithms - Answers result will have the same number of decimals as there are sig figs in
the logarithm.
Density - Answers mass/volume
intensive property - Answers do not depend on the amount of substance present
extensive property - Answers do depend on the amount of substance present
how many cm are in one inch? - Answers 2.54
law of conservation of mass - Answers mass is neither created nor destroyed in a chemical reaction
who developed the law of conservation of mass - Answers Lavoisier
law of definite proportions - Answers a given compound always contains exactly the same proportion
of elements by mass
who founded the law of definite proportions? - Answers Joseph Proust
Law of Multiple Proportions - Answers whenever two elements form more than one compound, the
different masses of one element that combine with the same mass of the other element are in the
ratio of small whole numbers
daltons atomic theory - Answers 1) elements are composed of atoms. 2) atoms of same element are
identical, but differ from other elements. 3) chemical compounds form when elements combine 4)
chemical reactions reorganize atoms, but the atoms don't change themselves.
JJ Thomson's cathode ray tube experiment - Answers - Around 1900, JJ Thomson used a cathode ray
tube to produce particles that we now call electrons.
- Took particles and shot it though two electric plates. Repelled by the negative field, so electrons
must be negatively charged.
- Used a magnetic field to determine the charge to mass ratio: -1.76e10 8 C/g
- Because these electrons could be produced from all metals, he concluded that every element must
contain electrons.
- If atom is neutral, then there must be some positively charged particle -> Plum Pudding Model.
Millikans Oil Drop Experiment: - Answers Millikans Oil Drop Experiment:
- Sprayed Oil on two electron plates. Charge of the electrons: -1.60e-19 C
- Using this new charge and the charge to mass ratio found by Thomson, he found the mass of the
electron: 9.11e-31 kg
Rutherford's Gold Foil Experiment: - Answers Rutherford's Gold Foil Experiment:
- Wanted to test the validity of Thomson's Plum Pudding Model.
