Properties of Matter: Physical Properties Return to Table of Contents

Physical Properties Every type of matter has two kinds of properties: physical and chemical. A physical property is a characteristic that can been observed without changing the substance into a new one. Physical properties include: hardness, texture, density, flexibility, color, the ability to dissolve, magnetism, melting point, boiling point and the substance's physical state (solid/liquid/gas). Name some physical properties of this brick wall.

Using Physical Properties to Identify Substances Some physical properties of substances are unique. Therefore, these properties can be used to determine mystery objects. Imagine if someone wanted to sell you this "gold" coin. You can use the known physical properties of gold in order to test if the seller is telling you the truth. We will be looking at the physical properties of various elements in the Periodic Table.

Physical Properties of Elements Elements of the same group are sometimes said to be in the same family. This is because elements that are grouped together often have similar properties. Below, the elements are grouped into their respective families. H 1 Nonmetals Alkali Metals Alkaline Earth Metals Other Metals Metalloids B Si Ge As Sb Te Po Halogens Noble Gases Transition Metals Lanthanides Actinides

Metals Look around the room. How many objects do you see that are made of metal? What are some physical properties of the metals you see? Remember: Physical properties include hardness, texture, flexibility, color, the ability to dissolve, magnetism and if the object is solid, liquid, or gas.

Properties of Metals Metals are malleable which means they are able to be hammered or rolled into flat sheets or shapes. Some metals are attracted to magnets.

Properties of Metals Metals are ductile so they are able to be pulled or stretched out into long wire. Most metals are good conductors, so they transfer heat and electricity well.

Families of the Periodic Table The following slides will introduce the various families of the Periodic Table as well as list some general characteristics of elements that are a part of each family. Remember, elements of the same family have similar traits. Use the link below to print blank copies of periodic table to fill in and color as you discuss families. Be sure to include a key on your paper. Click here for a blank printable Periodic Table of Elements.

Alkali Metals vs Alkaline Earth Metals Elements that are found in Group 1 are called Alkali Metals. Elements in Group 2 are called Alkaline Earth Metals. Not only are their names similar, but their properties are as well: Alkali Metals Alkaline Earth Metals React by losing 1 electron React by losing 2 electrons Never found uncombined in nature Most reactive metals 2nd most reactive metals Sodium (Na) and Potassium (K) most important Alkali metals Magnesium (Mg) and Calcium (Ca) most important Alkaline Earth metals *We will be looking more at how elements react with each other in the 2nd Unit of this school year! Do you notice anything similar about the names of the elements in these two groups?

18 Does malleability mean a metal can be hammered into a flat sheet? Yes No Answer

18 Does malleability mean a metal can be hammered into a flat sheet? Yes No Answer

19 Alkali Metals react with other elements by gaining one electron. True False Answer

19 Alkali Metals react with other elements by gaining one electron. True False- they lose one electron Answer

Transition Metals Transition Metals are in Groups 3 through Group 12. Transition metals are less reactive than Groups 1 & 2. They are hard and shiny and are usually good conductors of electricity. Color and label this section.

Color and label this section. Lanthanides Lanthanides are actually a part of Period 6, but they are typically moved to the bottom of the Periodic Table to make it easier to read. or They are usually soft, malleable, shiny metals that have high conductivity. They are mixed with other metals to make alloys; a mixture of a metal with at least one other element, usually another metal. Color and label this section.

Actinides Below the Lanthanides, you can find the Actinides, which are a part of Period 7. or Only four elements in the Actinides occur naturally on earth. They are Actinium, Thorium, Protactinium and Uranium. All other elements, heavier than uranium, were created artificially in labs. The nucleus of each of these elements is unstable causing it to break apart. Uranium is used in nuclear energy. Color and label this section.

"Other Metals" and Metalloids Some of the elements in Groups 13 through 15 are metals. They are not as reactive as the metals on the left side of the table. Metalloids are elements that are similar to both metals and nonmetals. They are hard, brittle and can conduct electricity. "Other Metals" are in gray. "Metalloids" are in olive green.

A nonmetal is an element whose properties are opposite of metals. Nonmetals A nonmetal is an element whose properties are opposite of metals. Most nonmetals are poor conductors of heat and electricity. Solid nonmetals are brittle (break easily) and dull. Don't forget about Hydrogen (H)! Color and label this section.

Halogens The Halogen family (found in Group 17) is the most reactive nonmetal group. The elements in this group are dangerous to humans when uncombined. The physical properties of these elements vary ­ some elements are solids, some are liquids and some are gases at room temperature! Bromine ­ a liquid Chlorine ­ a colorless gas Iodine ­ a solid Notice that all of the halogens end in ­ine!

The Noble Gases The elements in Group 18 are known as Noble Gases. Noble gases do not gain, share or lose electrons, which means that they do not react with other elements. Krypton Xenon Neon What do the names of all of the Noble Gases end in?

20 All of the elements in Group 18 will be a room temperature. Solid A Answer Liquid B Gas C

20 All of the elements in Group 18 will be a room temperature. Solid A Answer Liquid B Gas C

21 A useful property of a metalloid is itsability to conduct electricity. True False Answer

21 A useful property of a metalloid is its ability to conduct electricity. True False Answer

22 Noble gases react very easily with other elements. True False Answer

22 Noble gases react very easily with other elements. True False – they do not react easily with other elements Answer

23 Where on the periodic table are the metals found? transition 23 Where on the periodic table are the metals found? A Far right Answer B Middle C Far left

23 Where on the periodic table are the metals found? transition 23 Where on the periodic table are the metals found? A Far right Answer B Middle C Far left

Compounds The Physical Properties mentioned on the previous slides apply to all pure substances. This includes both elements and compounds . A compound is formed when two or more different elements join together, or "bond." For example: H2O is made up of Hydrogen and Oxygen atoms. H O H

Molecules A molecule is the smallest possible part of a compound. Just like an atom is the smallest possible part of an element, a molecule is the smallest possible part of a compound. This box is filled with the compound "water." Each individual part of this compound is called a molecule of water.

Molecules Molecules are formed when one or more atoms chemically bond together. Water is formed when 2 Hydrogen atoms and 1 Oxygen atom combine. H H 2 Hydrogens H O 1 Oxygen O H It is important to realize that when these two elements combine to form water, their properties change. Hydrogen and Oxygen on their own are completely different than water. H O H

Molecules The structure of molecules can range from two or more of the same atoms or two or more different atoms. O Na Cl O O Ozone ­ O3 Salt ­ NaCl Glucose (Sugar) ­ C6H12O6

Build a Molecule: Water H2O We know this is a compound because it includes more than just 1 atom. This is a compound because two different elements are combining. What do the H and the O stand for in the chemical formula above? H ­ O ­

Build a Molecule: Water H2O Oftentimes in a chemical formula, you will see a small number after the element symbols. This number is called the subscript. This number tells you how many atoms of each element there are in the compound. The number goes along with the element before it. If there is no number, then there is one atom of that element. How many H atoms are there? ­ How many O atoms are there? ­

Ratio of Atoms A molecule is represented by a chemical formula which shows the elements in the compound and the ratio of atoms in that specific compound. Carbon Dioxide: CO2 # of C atoms = 1 2 # of O atoms = RATIO of Carbon to Oxygen: 1:2

24 What is the ratio of Carbon atoms to Hydrogen atoms in Propane (C3H8)? Answer

24 What is the ratio of Carbon atoms to Hydrogen atoms in Propane (C3H8)? Answer

25 What is the ratio of Nitrogen atoms to Hydrogen atoms in Ammonia (NH3)? B 1:3 Answer

25 What is the ratio of Nitrogen atoms to Hydrogen atoms in Ammonia (NH3)? B 1:3 Answer