Matter & Chemical Change Flashcards
study for test
what are the 3 ways of classifying materials based on their composition and properties
Pure substance: Have uniform composition.
Solution: Homogeneous mixtures of two or more substances. Example: salt water.
Mechanical mixture: Heterogeneous mixtures with visible different parts. Example: sand and water.
what are the differences of metals and non metals
Metals: Generally shiny, good conductors of heat and electricity, malleable and ductile. Example: Iron.
Non-metals: Opposite properties of metals. Example: Oxygen.
how do you find density, hardness, magnetism, and solubility
Density: materials based on mass per unit volume.
Hardness: materials based on resistance to scratching or deformation.
Magnetism: materials based on attraction to magnets.
Solubility: materials based on ability to dissolve in a solvent.
how would a material be changed, & how to evaluate if a new substance has been produced.
Change in properties: Occurs under conditions like heat, pressure, or chemical reactions.
New substance: Produced if there’s a change in color, formation of gas, or formation of a precipitate.
what are caustic materials and what is a explosive reaction
Caustic materials: Can cause burns and eye damage. Example: Sodium hydroxide.
Explosive reactions: Rapid release of gas and heat. Can cause harm due to shock waves. Example: Dynamite explosion.
how do you distinguish between materials that react rapidly and those that do not.
Reactive materials: React rapidly with other substances. Example: Sodium.
Non-reactive materials: Do not react or react slowly. Example: Gold.
what is a exothermic reaction and what is a endothermic reaction.
Exothermic reactions: Release heat. Example: Combustion.
Endothermic reactions: Absorb heat. Example: Photosynthesis.
what is matter
anything that has mass and takes up space
what is a mixture
more than one pure substance combined
what is a ionic bind
a bind between two atoms where one or more are metal
what is a pure substance
made of atoms, molecules and ions which react or act as one pure substance
what is heterogenous
(HE) components of mixture are easily seen, ex oil with water
what is homogenous
it means that it you cant see a difference in a substance with two liquids mixed into it, example sugar and water
what is a compound
two or more atoms combined together
what are atoms
they are building blocks composed of protons, neutrons and electrons
what is ionic
formed by a positive and negative
what is molecular
it is formed by atoms sharing electrons
what’s physical properties
a physical thing that can be observed
what chemical properties
a chemical thing that can not be observed by the five senses
what is physical changes
physical properties that alter the physical look but not the composition
what’s chemical changes
when it transforms into one or more new substances
what are protons
positively charged atoms
what are neutrons
they are neutral charged
what are electrons
they are negatively charged
