CHEMISTRY 141 EXAM #1
QUESTIONS & ANSWERS|| 2025
LATEST UPDATE
Chemistry - ANSWERThe study of matter
Atom - ANSWERThe simplest form of matter that retains the identity of that matter
Carbon - ANSWERElement of life
Compound - ANSWERA substance composed of two or more different elements
Molecule - ANSWERA unit of matter that is composed of two or more atoms
Mixture - ANSWERComposed of two or more pure substances of variable composition
Homogenous Mixture - ANSWERUniform throughout
Heterogenous Mixture - ANSWERNot uniform throughout
Solid - ANSWERFixed shape and fixed volume
Liquid - ANSWERVariable shape and fixed volume
Gas - ANSWERVariable shape and variable volume
Melting - ANSWERConversion of solid to liquid
Deposition - ANSWERConversion of gas to solid
Evaporation - ANSWERConversion of liquid to gas
Condensation - ANSWERConversion of gas to liquid
Freezing - ANSWERConversion of liquid to solid
Sublimation - ANSWERConversion of solid to gas
Physical Property - ANSWERCan use senses to determine
Chemical Property - ANSWERHow substances react to other substances, changes
composition of substance
, Mass - ANSWERThe quantity of matter in a sample
Freezing Temperature - ANSWER0=C 273=K
Boiling Temperature - ANSWER100=c 373=K
Significant Figures when +/- - ANSWERThe # of decimal places in the number with the
fewest places
Significant Figures when * or / - ANSWERThe # of significant figures in the number with
the fewest significant figures
Kilo - ANSWER10³
Centi - ANSWER10⁻²
milli - ANSWER10⁻³
micro (u) - ANSWER10⁻⁶
Law of Conservation of Mass - ANSWERDuring a chemical reaction mass is conserved
Law of Constant Proportions - ANSWERDuring a chemical reaction proportions are
conserved
Law of Multiple Proportions - ANSWERDuring a chemical reaction ratios are conserved
Atomic Theory - ANSWER1)All matter is composed of atoms 2)All atoms of the same
element have identical chemical properties 3)Atoms form chemical compounds by
combining in whole number ratios 4)Atoms are neither created nor destroyed
Dynamic Equilibrium - ANSWERParticles are constantly moving back and forth at the
same rate so it keeps equilibrium
Electrical Force - ANSWEROpposites attract, same charges repel
Gas Discharge Experiment - ANSWERConclusion was that atoms contain smaller parts
that possess positive and negative charges
J.J. Thompson's Experiment - ANSWERDetermined the ratio of the charge and mass of
electrons to be -1.76 x 10¹¹ C/kg
Four types of Forces - ANSWERGravitational, Electromagnetic, Strong nuclear, Weak
nuclear
QUESTIONS & ANSWERS|| 2025
LATEST UPDATE
Chemistry - ANSWERThe study of matter
Atom - ANSWERThe simplest form of matter that retains the identity of that matter
Carbon - ANSWERElement of life
Compound - ANSWERA substance composed of two or more different elements
Molecule - ANSWERA unit of matter that is composed of two or more atoms
Mixture - ANSWERComposed of two or more pure substances of variable composition
Homogenous Mixture - ANSWERUniform throughout
Heterogenous Mixture - ANSWERNot uniform throughout
Solid - ANSWERFixed shape and fixed volume
Liquid - ANSWERVariable shape and fixed volume
Gas - ANSWERVariable shape and variable volume
Melting - ANSWERConversion of solid to liquid
Deposition - ANSWERConversion of gas to solid
Evaporation - ANSWERConversion of liquid to gas
Condensation - ANSWERConversion of gas to liquid
Freezing - ANSWERConversion of liquid to solid
Sublimation - ANSWERConversion of solid to gas
Physical Property - ANSWERCan use senses to determine
Chemical Property - ANSWERHow substances react to other substances, changes
composition of substance
, Mass - ANSWERThe quantity of matter in a sample
Freezing Temperature - ANSWER0=C 273=K
Boiling Temperature - ANSWER100=c 373=K
Significant Figures when +/- - ANSWERThe # of decimal places in the number with the
fewest places
Significant Figures when * or / - ANSWERThe # of significant figures in the number with
the fewest significant figures
Kilo - ANSWER10³
Centi - ANSWER10⁻²
milli - ANSWER10⁻³
micro (u) - ANSWER10⁻⁶
Law of Conservation of Mass - ANSWERDuring a chemical reaction mass is conserved
Law of Constant Proportions - ANSWERDuring a chemical reaction proportions are
conserved
Law of Multiple Proportions - ANSWERDuring a chemical reaction ratios are conserved
Atomic Theory - ANSWER1)All matter is composed of atoms 2)All atoms of the same
element have identical chemical properties 3)Atoms form chemical compounds by
combining in whole number ratios 4)Atoms are neither created nor destroyed
Dynamic Equilibrium - ANSWERParticles are constantly moving back and forth at the
same rate so it keeps equilibrium
Electrical Force - ANSWEROpposites attract, same charges repel
Gas Discharge Experiment - ANSWERConclusion was that atoms contain smaller parts
that possess positive and negative charges
J.J. Thompson's Experiment - ANSWERDetermined the ratio of the charge and mass of
electrons to be -1.76 x 10¹¹ C/kg
Four types of Forces - ANSWERGravitational, Electromagnetic, Strong nuclear, Weak
nuclear
