Chemistry: Element Lab

Physical and chemical properties can be used to classify and identify substances. 

Metals and nonmetals are two major groups of elements that have different physical properties. 

 Physical properties of metals include: 

● Luster—Having a shiny surface or reflecting light brightly 

● Conductors—Heat and electricity move through them easily 

● Malleable—Ability to be hammered into different shapes 

● Ductile—Ability to be drawn into a wire 

● High density—Heavy for their size 

 Physical properties of nonmetals include: 

● Dull—Not shiny 

● Nonconductors—Heat and electricity do not move through them easily 

● Brittle—Break or shatter easily (solids) 

Physical properties can be observed and measured without changing the kind of matter being studied. The following physical properties can be used to help identify a substance:

Melting Point: 

● The temperature at which a solid can change to a liquid 

● Unchanging under constant conditions 

● Example: Ice melts to form liquid water at 0 oC (32o F). 

Boiling Point: 

● The temperature at which a liquid changes from a liquid to a gas. 

● Boiling begins when bubbles form throughout, grow larger, rise to the surface, and burst. 

● As long as the substance is boiling the temperature of the liquid remains constant (at the boiling point). 

● Boiling point is unchanging under constant conditions for a given substance. 

● Example: The boiling point for pure water at sea level is 100oC ( 212o F). 

Density: 

● The relationship between the mass of a material and its volume 

● Substances that are denser contain more matter in a given volume

●The density of a substance is unchanging no matter how large or small the sample of the substance. 

● Example: ○ Lead is a very heavy, dense metal. The density of lead is much greater than the density of the very light metal, aluminum. ○ Generally, metals have a heavier density than nonmetals. 

Conductivity: 

● The ability to act as an electrical conductor or an electrical insulator is based on the solid’s ability to complete an electric circuit, i.e., conduct electricity. 

● Materials with high conductivity are called electrical conductors because they allow current to flow easily. 

● Materials with low conductivity are called electrical insulators (nonconductors) because they do not allow current to flow. 

● Example: Most metals are electrical conductors while nonmetals are electrical insulators. 

Color: 

● Color can be used to help identify a substance, along with other properties. 

● By itself, color is not a significant identifier of a substance. 

● Absence of color is also a physical property. 

Hardness: 

● The relative resistance of a metal or other material to denting, scratching, or bending. 

Magnetism:

● The property of reacting to the forces exerted by magnets