Periodic Table
The number of electrons Strontium (Sr) has
38 electrons
Definition of an element
A substance whose atoms are all alike
Type of bond that transfers electrons
Ionic
Definition of simple machines
The 3 main categories that the elements can be split into.
Metals, nonmetals, and metalloids
Direction of a period on the periodic table (left to right or up and down)
Left to right (7 periods)
Definition of condensation
Explain why valence electrons are important in chemical reactions
They are the outer electrons that are involved in bonding and forming new compounds/substances. The number of valence electrons determine how reactive an element is and its desire to become more stable (virtually all elements desire 8 valence electrons)
Definition of a force
A push or pull exerted on an object that causes a change in motion, has moth magnitude and direction.
Definition of amplitude of a wave
The maximum displacement an object moves from equilibrium
Definition of an isotope
An atom that has more or less neutrons that the normal atom of that element
Name an example of a suspension
Name the types of bonds that form between--
2 nonmetals:
1 metal and 1 nonmetal:
2 metals:
Covalent
Ionic
Metallic
The type of simple machine that pivots around a fulcrum
Lever
Definition of a longitudinal wave
A wave in which the disturbance is in the same direction, or parallel to, the direction of wave motion
Definition of electronegativity and the trend as you go across the periodic table and down the periodic table
Electronegativity: the ability to attract the electrons of another atom
Across: increases
Down: decreases
Description of the Tyndall Effect and what kind of substance causes it to occur.
The scattering of light by colloidal particles
Balance the following chemical equation and identify the products and the reactants:
__ H2 + __O2 --> __ H2O
2 H2 + 1 O2 (reactants)--> 2 H2O (products)
Inclined plain
The families on the periodic table that are most reactive and the reason why
Alkali metals and/or halogens are most reactive because they are very close to having a full outer shell. Alkali have to lose 1 electron, halogens have to gain 1 electron.
Draw the Bohr model and the Lewis Dot Diagram for Nitrogen (N)
Lewis: N with 5 dots around it (5 valence electrons)
The difference between a physical and chemical change, with an example of each
Physical changes are reversible and do not change the composition of the substance. Chemical reactions are usually irreversible and change the arrangement of atoms to form new substances (chemical reactions).
Draw a ionic bond and a covalent bond.
Ionic transfers (1 nm & 1 m), covalent shares (2 nm)
Name 3 types of simple machines and an example of each.
Wheel and axle, inclined plane, wedge, lever, pulley, and screw
Name at least 5 families on the periodic table
Alkali metals, alkaline earth metals, transition metals, boron family, carbon family, nitrogen family, oxygen family, halogen family, noble gas family, inner transition metals.