Lewis Dot Structures
What do Lewis dot structures show?
The valence electrons of an atom.
What does the pH scale measure?
How acidic or basic a substance is.
What are the three common states of matter?
Solid, liquid & gas.
What type of change affects the form of a substance but not its identity?
Physical Changes
What is the periodic table organized by?
Atomic Number
How many valence electrons does oxygen have?
6
What number on the pH scale is neutral?
7
Which state of matter has a definite shape and definite volume?
Solid
Which type of change produces a new substance?
A Chemical Change
As you move from left to right across a period, does atomic size generally increase or decrease?
Decrease
How many valence electrons does oxygen have?
4
Is a substance with a pH of 3 acidic or basic?
Acidic
Which state of matter has a definite volume but no definite shape?
Liquid
Is melting ice a physical change or a chemical change?
Physical Change
Elements in the same column have the same number of what?
Valence Electrons
Which element has one valence electron and forms one dot in its Lewis structure?
Hydrogen
Which is more acidic: a substance with pH 2 or pH 5?
pH 2
What process changes a liquid into a gas?
Evaporation
Rusting of iron is an example of what type of change?
Chemical Change
Which group on the periodic table is the most reactive metals?
Group 1
Why do atoms form bonds in Lewis dot structures?
To fill out their energy level and be stable.
If a solution has a pH greater than 7, what type of substance is it?
A base
What is the state of matter in which particles are ionized and conduct electricity?
Plasma
Name one sign that a chemical change has occurred.
temperature change
As you move down a group on the periodic table, what happens to atomic size?
It increases