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