Atoms A
What is the study of matter?
Chemistry
How do scientists calculate the atomic mass of an atom?
by adding protons and neutrons
What tells the number of protons in an atom?
atomic number
What languages are used for the chemical symbol?
English and Latin
The atomic number shares the number of protons. What else does the atomic number share?
the number of electrons
What is a group of atoms joined together?
a molecule
What is the process through which different types of atoms join together?
chemical reaction
What part of atoms allows compounds to be made?
the outer shell
What is a compound that forms hydrogen ions when dissolved in water?
acids
What is the smallest piece of an element that still can be recognized as that element?
an atom
What particle of an atom has a negative charge?
Are they stationary or moving?
electrons
moving
How are the elements arranged in the periodic table?
They are in order by their atomic number.
What is the proper way to write a Chemical symbol if it has two letters?
The first is capitalized and the second is lowercase.
What are the horizontal rows of the periodic table?
What do the rows tell you?
periods
Each element in that row has the same number of shells.
What kind of molecule is formed from the same kind of atoms?
diatomic molecule
Which reaction causes a new substance to be formed?
synthesis reaction
What does it mean when atoms are stable?
What gases are stable?
It means they will probably not form compounds with other atoms.
Noble gases
What are 2 characteristics of an acid?
What are substances that are made up of one kind of atom?
elements
Why do normal atoms usually have a balance of charges?
the number of protons and electrons are equal
Who was one of the founders of the atomic structure?
What war did he live through?
What did he help develop?
Niels Bohr
WWII
atomic bomb
Who is the scientist who developed the classification system?
Dmitri Mendeleev
What is the name of the columns of the periodic table?
What information does this share?
groups
Each element in the group has the same number of electrons in the outer shell.
What process happens when different atoms join together?
What kind of molecule is made?
chemical change or chemical reaction
a compound
Which reaction allows substances to break down into simpler substances?
decomposition reaction
Which bond happens when atoms share electrons?
Which substances usually have this bond?
covalent
gases and liquids
What is a compound that forms hydroxide ions when dissolved in water?
What are some characteristics?
Name one example.
bases
bitter tasting, slippery
baking soda, bleach, ammonia
What are the 3 main parts of an atom?
What are their charges?
protons-positive
neutrons-neutral or no charge
electrons-negative
What is the maximum number of electrons in the first shell of an atom?
What is the maximum number of electrons in the second shell of an atom?
2 electrons
8 electrons
What term is used to describe what scientists think about atoms?
Why do scientists not know exactly what atoms look like?
Atomic Theory
They are too small for the human ey to see.
How is it organized now?
by atomic mass or weight
by its atomic number
Name 3 of the 10 categories of elements.
How are they classified?
Alkali metal, transition metal, metalloid, halogen, lanthanide, alkaline earth, basic metal, nonmetal, noble gas, actinide
by similar physical and chemical properties. they are grouped by colors
What is the most common compound?
What is it made of?
water
2 hydrogen atoms, 1 oxygen atom
Which reaction happens when one element replaces another element?
single replacement
What is it when an atom has gained or lost an electron?
When an atom has more electrons, what charge does it have?
When an atom has more protons, what charge does it have?
ions
negative
positive
What is a base that dissolves in water?
What numbers on the pH scale show an acid?
What numbers on the pH scale show a base?
alkali
0-6.9
7.1-14
What is the center of an atom?
What particles make up the center of an atom?
nucleus
protons and neutrons
Why is it important for electrons to move freely around the nucleus?
It allows for atoms to bond with other atoms to form substances.
What is the machine scientists use to smash atoms?
Name one subatomic particle from atoms being smashed into smaller particles.
quarks, leptons, mesons, pions, and gravitons
What 4 pieces of information can be found on an element card?
What is one characteristic of a metal?
solid at room temp, high temp to melt, good conductors of heat and electricity
What is the chemical symbols and numbers that show the elements that make up a compound?
What do the small numbers tell us?
chemical formula
the number of atoms of each element are in a compound
Which reaction happens when two elements switch places?
double replacement reaction
What bond happens when diffent ions join together?
Why does this bond happen?
ionic bond
It is similar to the poles on a magnet. Opposite charges attract and form crystals.
What do gardeners do to increase soil pH?
What do gardeners do to decrease soil pH?
What is an ionic compound formed from the reaction between an acid and a base?
What is this substance composed of?
add lime or another base
add compost or peat moss
salt
a metal and a nonmetal