Structure of matter and the Periodic Table

Atoms are made of Protons Neutrons Electrons - positive -no charge - Part of the atomic mass - Atomic number Neutrons -no charge -part of mass -make isotopes different Electrons -negative charge -valence electrons used to make chemical bonds

1. Which of the following best describes an atom? A: protons and electrons grouped together in a random pattern B: protons and electrons grouped together in an alternating pattern C: a core of protons and neutrons surrounded by electrons D: a core of electrons and neutrons surrounded by protons

2. Which of the following is farthest from the center of an atom? A: nucleus B: proton C: neutron D: electron

3. What characteristic is different in each isotope? A: the position in the periodic table of the elements B: the number of neutrons in the nucleus C: the net charge of the nucleus D: the mass of the protons in the nucleus Isotope Atomic mass Ca-40 40 Ca-42 42 Ca-43 43

Compounds Compounds are made by combining two or more different elements H2O To read a compound find the Capital letters Hydrogen and Oxygen

The properties of a compound are different from the original elements Hydrogen (H) Oxygen (O) Carbon (C) Sugar C6H12O6

4. When magnesium (Mg) metal is burned in the presence of oxygen (O2), magnesium oxide (MgO) is produced. The properties of magnesium oxide are different than the individual properties of magnesium and oxygen because magnesium oxide is A: a solution B: a mixture C: a compound D: an element

5. Iron oxides, such as rust, form when metal reacts with oxygen in the air. What are the chemical symbols for the two elements found in iron oxide? A: Fe and O B: Ir and O C: I and O D: Pb and O

6. What is the name of the atom in the acetic acid molecule shown? A: Carbon B: calcium C: chromium D: copper

The Periodic table is organized: Metals to the left and non-metals to the right of the zig-zag line Metals and non-metals have opposite properties Metals Non-metals High density Low density High melting and boiling points Low melting and boiling points Good conductors of heat and electricity Bad conductors of heat and electricity Shiny and ductile Dull and brittle

7. What do the elements Lithium (Li), manganese (Mn), iron (Fe) and californium (Cf) have in common? A: they are noble( inert) gases B: they are nonmetals C: they are metals D: they have the same number of protons

8. Which class of elements best conducts electricity? A: metals B: nonmetals C: semimetals D: noble (inert) gases

9. In a comparison of metals to nonmetals, metals tend to have A: lower melting points and greater conductivity than nonmetals B: lower conductivity and lower density than nonmetals C: higher density and lower melting points than nonmetals D: greater conductivity and higher melting points than nonmetals

10. A student divides several cubes into two groups, based on whether or not each cube can float in water. What property is the student using to classify the cubes? A: weight B: density C: conductivity D: mass

States of matter are determined by molecular motion

States of matter are determined by molecular motion Solids -are closely locked into position and can only vibrate -they have a specific volume and shape Liquids -atoms and molecules are more loosely connected and can move past each other they have a specific volume but can change shape Gases -atoms and molecules are free to move independently, colliding (bumping) frequently -they have no specific volume or shape

11. Within a substance, atoms that collide frequently and move independently of one another are most likely in a A: liquid B: gas C: solid D: crystal

12. Which change in phase does the picture best represent? A: solid to liquid B: gas to solid C: gas to liquid D: liquid to gas