Chem test 1 Flashcards
What is chemistry?
The study of matter and the changes it undergoes
In practice, there is a lot of _______ between the various chemical disciplines
Crossover
What is matter?
Anything that has mass and occupies space
What are atoms?
submicroscopic particles that are the fundamental “building blocks” of all matter
What are protons?
positively charged particle
What are neutrons?
electrically neutral particle with about the same mass as a proton
What are electrons?
a negatively charged particle with very small mass
What is a molecule?
Two or more atoms joined together
If matter is comprised of a pure substance and cannot be separated into simpler subunits, then that matter is called an
element
if matter is a pure substance and is composed of two or more elements then the matter is called a
compound
if matter is consisting of 2 or more pure substances and has a uniform composition and properties, the matter is called
homogenous mixture
if matter is consisting of 2 or more pure substances and has a composition and properties that are not uniform, the matter is called a
Heterogeneous mixture
Define deposition
from a gas to a solid (think frost)
Define sublimation
from a solid to a gas (think dry ice)
What are the properties displayed in a physical change?
MOCTAB
melting point
odor
color
taste
appearance
boiling point
What are the properties displayed in a chemical change?
FACT
Flammability
Acidity
Corrosiveness
Toxicity
Who developed the atomic theory?
John Dalton 1808
What is the atomic theory?
- each element is composed of atoms
- all atoms of a given element have the same mass and other properties that distinguish them from other atoms in other elements
- atoms combine in simple, whole number ratios
- Atoms cannot change into atoms of another element, they just change how they are bound to create a new substance
Where and how are protons and neutrons bound?
In the nucleus by a strong nuclear forces
How are electrons bound to the nucleus?
By electromagnetic forces (opposites attract)
Group 1 of the periodic table are
alkali metals
group 2 of the periodic table are the
alkaline earth metals
group 3-12 are the
transition metals
group 17 are the
hallogens
group 18 are the
noble gasses
The atomic number shows
the number of protons in an element. Also equal to the number of electrons in an element
the mass number is
the sum of the number of protons and neutrons
atomic mass is
the average mass of an element based off of the masses of all of the isotopes that make up the element. Weighted according to the natural abundance of each isotope
molar mass is
the mass of a given element divided by the amount of substance
The mass of 1 molecules of any substance
The group number tells us how many ______ there are
valence electrons
What are the metalloids?
Boron
Silicon
Arsenic
Tellurium
Astatine
Germanium
Antimony
What does electron configuration tell us?
The exact orbital occupied by electrons within an atom. It us used to calculate the probability of finding an electron in a specific region around the nucleus.
What are the 3 electron configuration shapes we talked about?
S- sphere
P- figure 8
D- 4 leaf clove
What are core electrons?
Electrons found in the innermost circles to the the nucleus. These are the lowest energy levels
What are valence electrons?
Electrons found in the outermost circles to the the nucleus. These are the highest energy levels
What is the Aufbau principle?
Electrons are placed into the lowest energy orbitals first.
How do you find the number of neutrons?
Subtract the atomic number from the atomic mass.
how many electrons can the s orbital hold?
2
how many electrons can the p orbital hold?
6
how many electrons can the d orbital hold?
10
How can you double check that you have added the correct number of electrons to your electron configuration?
add all of the hyperscript numbers. this should equal the number of electrons.
How do you know which electrons in the electron configuration are valence electrons?
These are the electrons found in the highest energy levels. You can find the number of valence electrons by looking at the group number (groups 13-18 subtract 10)
If your isotope configuration is the same configuration as a noble gas, how do you write the noble gas shortcut?
By using the previous noble gas in brackets and listing all of the electron orbitals after that.
An atom that has gained an electron is called an
anion (nonmetal)
In anions you have to _____ electrons to your configuration
add
An atom that has lost an electron is called a
Cation (metal)
In cations you have to _____ electrons to your configuration
subtract
What are the atomic size trends?
INCREASES down and to the left
What are the electronegativity trends?
DECREASES down and to the left
What is electronegativity?
the ability to attract electrons
Br
Bromine
I
Iodine
Fe
Iron
Co
Cobalt
Ni
Nickel
Cu
Copper
Zn
Zinc
Ag
silver
Au
gold
Pt
platinum
Hg
mercury
Ti
Titanium
Mn
Manganese
Sn
Tin
Pb
Lead
Cr
chromium
Cs
cesium
Sr
strontium
Ba
barium
What is the empirical formula?
simplest whole number ratio of a compound
what is the molecular formula?
exact number of each type of atom found in a compound
what is a structural formula?
exact manner in which the exact number of each type of atom is bound together
How to find the empirical formula from a structural and molecular formula.
From a structure determine each type of element in the structure.
Count the amount of each type.
Arrange in the CHXNOS arrangement
This is the molecular formula.
If you can reduce each element by the same whole number then do so
this is the empirical formula.
What is a molecular element?
More than one of the same element. (O2)
Ionic compounds are composed of one or more _______ and one or more ______
Metals (cation) and Nonmetals (anion)
H
Hydrogogen
He
Helium
Li
Lithium
Be
Beryllium
B
Boron
C
Carbon
N
Nitrogen
O
Oxygen
F
Fluorine
Ne
Neon
Na
Sodium
Mg
Magnesium
Al
Aluminum
Si
Silicon
P
Phosphorus
S
Sulfur
Cl
Chlorine
Ar
Argon
K
Potassium
Ca
Calcium
Molecular compounds are two or more _________
nonmetals
