Science Quiz #1 Flashcards
what are the 2 types of observations
quantitative and qualitative
define qualitative observations
- these are made using our senses
- they are descriptive but not very accurate
define quantitative observations
- these require a measuring tool or counting
- accurate, they do not depend on the person doing it observation
what are physical properties + give examples
- describe the observable properties of a substance
- do not change the substance
- Examples: size (mass, volume, density) shape, state, color, smell, texture….
define malleable
capable of being extended or shaped by beating with a hammer or by the pressure of rollers
define ductile
able to hammered thin or stretched into wire without breaking
define electrically conductive
the amount of electrical current a material can carry or it’s ability to carry a current
define thermally conductive
a substance’s ability to transfer heat through a material by conduction
define density
substance’s mass per unit of volume. (volume and mass)
define melting point
point at which a substance will melt. ex. melting point of ice is 0 degrees.
define viscosity
a measure of its resistance to deformation at a given rate
define brittleness
a material that breaks or fractures easily without much deformation or stress (ex. glass, raw egg)
define luster
describes how light is reflected on the surface of a mineral. ex. metals are shinny
define insulating
to cover, line, or separate with a material that prevents or reduces the passage, transfer, or leakage of heat, electricity, or sound
define opaque
not transparent
define transparent and translucent
transparent - not see through (ex. window)
translucent - kind of see through but not fully (ex. frosted glass)
here are some examples of physical properties!!
- Malleable
- Ductile
- Electrically Conductive
- Thermally Conductive
- Density
- Melting Point
- Viscosity
- Brittleness
- Luster
- Hard
- Insulating
- Magnetic
- Reflective
- Transparent
- Opaque
- Translucent
- Texture
- Powder
- Crystals
- Colour
define chemical properties
- Chemical properties refer to how reactive a substance is
- How a substance reacts when mixed with another
- Observations of chemical properties are impossible without a chemical change.
- Deals with atomic or molecular structures of a substance
define chemical properties these examples
(flammability, combustion, oxidation, reactivity)
flammability: how easily a vapor ignites
combustion: the product can burn
oxidation: reaction with oxygen to produce: -rust on iron or steel, grey tarnish on silver, or green stuff on old copper pennies
reactivity: how quick 2 substances react to create a new product.
evidence of physical change
o Change of state
o Dissolving
o Cutting
o Breaking
o Ripping
what is physical change
no new substance was made (ex. water into ice)
what is chemical change
a new substance with new properties formed (ex. chemical change)
evidence of chemical change
- Change in colour
- Gas forms (odour &/or bubbles)
- Change in temperature or light (change in energy)
- A precipitate (solid) forms from mixing of two
liquids - Change is irreversible
