Classifying Matter
What are the three states of matter?
Solid, Liquids, and Gases
What is a substance made of only one type of atom called?
Element
What physical property describes how easily a liquid flows?
Viscosity
What is a chemical change?
A change that produces one or more new substances
Is boiling water a physical or chemical change?
Physical
What is a pure substance?
Matter containing one type of particle or substance
What is a mixture?
Two or more substances physically combined, not chemically bonded
What property describes how well a material allows electricity to pass through it?
Conductivity
Is melting ice a physical or chemical change?
Physical
Which has a definite shape: a solid, liquid, or gas?
Solid
What is the difference between an element and a compound?
An element contains one type of atom; a compound contains two or more elements chemically bonded
What is a suspension?
A heterogeneous mixture with relatively large particles that can settle out
What property describes how much mass is packed into a certain volume?
Density
What property describes how easily a substance catches fire?
Flammability
A substance has a melting point of 80°C. What happens when it reaches 80°C?
It melts or changes to a liquid
What type of mixture has particles large enough to settle out over time?
Suspension
What is a colloid, and how is it different from a suspension?
A colloid has particles intermediate in size; unlike a suspension, its particles generally do not settle out
Which property would you use to determine whether a substance can be hammered into a thin sheet?
Malleability
What is a precipitate?
A solid that forms from a chemical reaction between substances in a solution
A student says, "If I can't see the particles, it's automatically a pure substance." Why is this statement incorrect?
Mixtures can look uniform even though they contain multiple substances; you cannot always determine composition just by looking
A beam of light is visible as it passes through a mixture, but the particles do not settle. What type of mixture is this?
Colloid — the particles are large enough to scatter light but small enough that they don't readily settle
A student mixes sand and water. After sitting for 10 minutes, the sand settles to the bottom. Is this a solution, colloid, or suspension? Explain why.
Suspension — the sand particles eventually settle to the bottom
Two objects have the same volume, but Object A has twice the mass of Object B. Which object has the greater density?
Object A
A clear liquid is mixed with another clear liquid. Suddenly, a solid forms at the bottom of the container. What evidence suggests a chemical change occurred?
Formation of a new solid/precipitate is evidence that a new substance may have formed
A mystery material is shiny, conducts electricity, can be hammered into sheets, and has a high melting point. Name two physical properties demonstrated by this material.
Conductivity and malleability (also potentially melting point if stated as a property)