Questions With 100% Correct Answers
2025/2026 Updated.
Observation - Answer __ - a way of acquiring information about nature
Hypothesis - Answer __- a tentative interpretation or explanation of an observation
Experimentation - Answer __- a test of a hypothesis, results either validate or invalidate the
hypothesis
Theories - Answer __- a general explanation for the characteristics and behavior of nature,
can be used to make predictions,
answers "Why does it happen?"
Laws - Answer __- summary of observations that combines all past observations into one
general statement, usually a
mathematical equation, answers "What will happen?"
1. Leading zeros are never significant
2. Trailing zeros are only significant if there is a decimal in the number
3. All non-zero numbers and zeros in the middle are significant - Answer Significant Digits 3
Rules:
answer is limited by the value with the fewest significant figures (total number of digits) -
Answer Multiplication and Division rules for significant digits
Answer limited by value with the most uncertainty (decimal place value) - Answer Addition
and Subtraction rules for significant digits
Dimensional Analysis - Answer __ __ - converting one quantity to another
1000m=1km - Answer __m=__km
, IL=1000mL - Answer __L=__mL
Density - Answer __ - a ratio of mass and volume
Pure Substances - Answer __ __ -A substance that cannot be broken into simpler substances
by physical processes
Examples: elements and compounds
Mixtures - Answer __ - two or more elements or compounds not bonded together, can be
broken down into components by physical
processes
Homogeneous Mixture - Answer __ __ the same throughout, evenly mixed, all samples will
look exactly the same, also called solutions.
Example: salt water, stainless steel, air
Physical Properties - Answer __ __ - characteristics of matter that can be changed without
changing its composition.
Example: boiling point, density, color, mass, volume
Chemical Properties - Answer __ __ -characteristics that determine how the composition of
matter changes as a result of contact with
other matter or the influence of energy
Example: reaction with oxygen, reactivity compared to other compounds or elements
Specific Heat - Answer __ __ - energy required to heat 1 gram 1 by 1 ˚C (units: J/g˚C)
Dalton: solid ball.
Thomson: discovered electrons, e- float in positive space.
Rutherford: discovered the nucleus, e- float around a small positive nucleus.
Bohr: used the emission spectrum of Hydrogen to create quantum theory. - Answer Models
of the Atom: Dalton, Thomson, Rutherford, Bohr