2.2 Physical Properties Key Concepts What are some examples of physical properties? How can knowing the physical properties of matter be useful? What processes are used to separate mixtures?

Examples of Physical Properties A physical property is any characteristic of a material that can be observed or measured ______________ ________________ the composition of the substances in the material. without changing Viscosity, conductivity, malleability, hardness, melting point, boiling point, and density are examples of physical properties.

Examples of Physical Properties Viscosity The tendency of a liquid to ________ from flowing is called its viscosity. ___________ liquids, such as corn syrup and honey, have a high viscosity. Thin liquids, such as vinegar and water, have a ________ viscosity. resist Thick low

Examples of Physical Properties Conductivity A material’s ability to allow ___________ to flow is called conductivity. Materials that have a high conductivity, such as _____________, are called conductors. Good conductors of heat are usually also good conductors of ______________ heat metals electricity

Examples of Physical Properties Malleability The ability of a solid to be __________________ without shattering is malleability. Most metals, such as _______________, are malleable. An ice cube or piece of glass breaks into small pieces when struck with a hammer. Solids that _______________ when struck are __________________, not malleable. hammered gold shatter brittle

Examples of Physical Properties Hardness One material can __________________ another material if it is harder than the other material. A kitchen knife can scratch a copper sheet because ___________ ______________ is harder than copper. The material used to sharpen the knife blade must be harder than stainless steel. ________________ is the hardest known material. scratch stainless steel Diamond

Examples of Physical Properties Melting and Boiling Points The temperature at which a material changes ___________ is a physical property. The temperature at which a substance changes from solid to liquid is its _________________ point. When ice ( frozen H2O) melts, does composition change? The temperature at which a substance changes from liquid to gas is its _______________________ point When liquid water (H2O) boils, does composition state melting No…it’s liquid water (H2O) boiling No…it’s water vapor (H2O)

Examples of Physical Properties Density The ratio of the ___________ of a substance to its __________ is its density. Less dense fluids will __________ on more dense fluids as long as they don’t mix mass volume float

Using Physical Properties Physical properties are used to _______________ a material, to _________________ a material for a specific purpose, or to _______________ the substances in a mixture. identify choose separate Ex: We choose to use _____________ shoelaces for hiking boots because it is a flexible yet durable material leather

Using Properties to Separate Mixtures Physical properties are also used to ________________ mixtures separate Filtration and distillation are two common separation methods.

Using Properties to Separate Mixtures Filtration Filtration is a process that separates materials based on the ____________ of their particles. Ex: You can separate hot tea from loose tea leaves by pouring the mixture through a ______________....or brewed coffee is separated from the grounds with a piece of filter __________________. size strainer paper

Using Properties to Separate Mixtures Distillation Distillation is a process that separates the substances in a solution based on their ________________ points. We can use distillation to separate… _________________ from fresh or tap water ________________ from sea water boiling impurities salt

What is the point of the condenser tube? To cool the vapor back down into liquid Where are the impurities trapped?

Recognizing Physical Changes During a physical change, the ________ and ____________ of a material can change but not the composition. Some examples include melting butter in a pan crumpling a piece of paper slicing a tomato Boiling water shape size

Recognizing Physical Changes Some but not all physical changes can be reversed. Braiding hair is a _______________ change. Cutting hair _____________ be reversed. reversible cannot

Which of the following is NOT a physical property? Assessment Questions Which of the following is NOT a physical property? density boiling point flammability conductivity

Which of these materials is not malleable? Assessment Questions Which of these materials is not malleable? copper aluminum glass gold

Assessment Questions 3. The process of filtration uses the difference in boiling points of substances to separate a mixture. True False - distillation