Lecture 5: Chemistry Review Flashcards
Atomic number (Z)
Number of protons, determines the identity of the atom
What are ions?
Atoms/groups of atoms bonded together with a net charge
Two types of ions
- Cations
- Anions
Cation
Positively charged ion
Anion
Negatively charged ion
Elements contain…
Only 1 type of atom
Compounds contain…
More than one kind of atom in a fixed ratio by mass
What are molecules?
Groups of atoms chemically bonded together into a discrete unit by covalent bonds; neutral charge
What are ionic compounds?
- Contain both positively and negatively charged ions with no identifiable units
- Attracted by charge and are not molecules
Can a substance be both a molecule and an element?
Yes
What is a physical change?
No change in the chemical makeup (i.e.: melting ice)
What is a chemical change?
Always makes a chemically different substance (i.e.: 2H2O —> 2H2 + O2)
What is a physical property?
May be observed/measured without changing the chemical makeup
What are two types of physical properties?
- Intensive
- Extensive
What is an intensive physical property?
Integral to the material, regardless of amount (i.e.: color)
What is an extensive physical property?
-Depends on sample size (i.e.: volume)
What is a chemical property?
Describes the type of chemical changes the material tends to undergo (i.e.: flammable)
Boiling water to steam
Chemical property
Liquid
Intensive physical property
Mass
Extensive physical property
What are substances?
Pure materials that can’t be physically separated into simpler components; can be compounds or elements
Throughout all samples, the chemical and physical properties of substances are ___
Uniform
What is a mixture?
2 or more pure substances
Physical processes can separate the mixture into ___
Simpler substances
Two types of mixtures
- Homogeneous
- Heterogeneous
What is a homogeneous mixture?
Uniform in physical and chemical properties throughout the whole sample (i.e.: normal saline)
What is a heterogeneous mixture?
Distinct phase boundaries where chemical and/or physical properties change (i.e.: emesis)
Protons and neutrons are in the ___
Nucleus
Electrons are located ___
Around the nucleus in cloud-like orbitals
Atoms have ___ properties rather than geometric properties
Wave-like
All atoms have ___ and ___
Protons and electrons
All atoms contain ___ except for ___
Neutrons except for hydrogen
Atomic Number (Z) =
Number of protons, determines identity
Ex: Carbon Z = 6
Neutron number (N) =
Number of neutrons
Mass number (A) =
Z + N
Atomic mass is measured in ___
Amu
Protons and neutrons are ~ ___ amu
~1 amu; leads to mass deficit
The mass number can never be smaller than…
The atomic number
What are isotopes?
Same atomic number, different mass number (diff number of neutrons, same number of protons)
Dalton’s Atomic Theory—Elements are composed of tiny, indivisible particles called ___. All atoms of a given element are…
Atoms; identical and unique to that element
Dalton’s Atomic Theory—Compounds are formed by…
Bonding atoms together in a fixed ratio
Dalton’s Atomic Theory—Chemical reactions do not ___, ___, or ___ … Chemical reactions cause atoms to…
Create, destroy, or change atoms into atoms of other elements; recombine into new substances
What is the Law of Conservation of Mass?
- No detectable change in the total mass occurs during a chemical reaction
- The components are neither created, nor destroyed—they recombine
What is the Law of Definite Proportions?
Different samples of a pure compound always contain the same elements in the same proportion by mass
Ex: Water = 11.2% hydrogen and 88.8% oxygen by mass
What is the Law of Multiple Proportions?
Some elements can combine to give more than one compound
Ex: Carbon burned in oxygen produces both carbon dioxide and carbon monoxide
What is the Periodic Law?
Properties of elements are periodic functions of their atomic numbers
The periodic table is arranged in order of…
Increasing atomic number
Vertical on the periodic table
Groups/families; similar chemical and physical properties
Rows on the periodic table
Periods
-Adding electrons to energy levels, electron shells
The element at the end of the row has the outer shell ___
Full of electrons
Elements with nearly full electron shells ___
Accept electrons
AKA anions
Elements with nearly empty electron shells readily ___
Release electrons
AKA cations
The atomic weights listed on the periodic table are ___
An average of all isotopes—no element is the exact weight listed
Representative elements are located…
In the high rises on the left and right
Transition elements are located between ___
the representative elements
Inner transition elements are located…
At the bottom of the table
Most elements are ___ and are on the ___ side of the table
Metals, left side
Properties of metals (5)
- Shiny luster
- Ductile
- Malleable
- Good conductors of heat and electricity
- React to form cations by giving away electrons
Ductile =
can stretch out; can stretch it out into a thin wire
Malleable =
Can pound it into submission; change its shape
Non-metals are located on the ___ side of the table
Right
Properties of non-metals (4)
- Liquids, solids, or gases
- Solids tend to be brittle
- Do not conduct
- Tend to form anions
Metalloids are located along ___
The ladder
Properties of metalloids (4)
- Intermediates
- Shiny luster
- Less malleable and ductile than metals
- Conduct electricity but not well—semiconductors
Most elements are ___
Solids
Mercury and bromine are ___
Liquids
Gallium will ___
Melt in your hand
Hydrogen, nitrogen, oxygen, fluorine, chlorine, and all noble gases are ___
Gases
What is electricity?
The flow of charged particles under the influence of an electric field
What is an electrolyte?
A substance that dissolves in water to give a solution conductivity
Most molecular compounds are considered ___
Non-electrolytes
Why does dissolution of electrolytes occur?
Because water interacts very effectively with ions
Water itself is a ___
Non-electrolyte
Aluminum (Al)
- Silvery white metal
- Low density
- Does not occur naturally in nature, must be synthesized
- Found in antiperspirants (aluminum chloride) and antacids (aluminum hydroxide)
Aluminum should be avoided in ___ patients
Dialysis patients—can build up and be toxic
Barium (Ba)
- Used in radiographic GI studies—barium sulfate oral solution or enemas
- Heavy metal, relatively opaque to x-rays
- Toxic, but patients will excrete the material fairly easily
Bromium (Br)
- One of 2 naturally occurring liquids
- Highly toxic
Calcium (Ca)
- Silvery white
- Doesn’t occur naturally in nature in the elemental form
- Muscle contraction, bone stability
- Found in antacids, phosphate binders
Carbon (C)
- Graphite and diamond occur naturally
- Activated charcoal—used in overdoses
- In most compounds, highly versatile
Chlorine (Cl)
- Toxic green gas
- Disinfectant
- Clorox, other cleaners
Chromium (Cr)
- Silvery white metal
- Forms highly colored compounds
- Found in stainless steel
Copper (Cu)
- Reddish metal
- Great conductor
Fluorine (F)
- Yellow, poisonous gas
- Sodium fluoride strengthens teeth
Helium (He)
- Colorless, inert gas
- MRI coolant
Hydrogen (H)
- Most common atom in the universe (> 95% of all known matter)
- Colorless, flammable gas
Iodine (I)
- Purplish/black solid
- Found in topical antiseptics and anti thyroid medications
Iron (Fe)
- Found in each hemoglobin molecule to transport oxygen through the blood
- Metal
Lithium (Li)
- Silvery, highly reactive metal
- Used as a mood stabilizer for bipolar patients
Magnesium (Mg)
- Silvery white metal
- Important for cardiac conduction and potassium levels
- Tocolytic therapy
- Laxative
Nitrogen (Ni)
- Colorless, odorless gas
- 80% of air
- Found in anesthetic gas as nitrous oxide (N2O)
Oxygen (O)
- Odorless, colorless, reactive gas
- Strong tendency to accept electrons, important in ATP synthesis
Phosphorus (P)
- Found in RNA and DNA and in ATP
- Low phosphorus may cause brittle bones and respiratory failure
- Supplemented in salt forms with sodium or potassium
Potassium (K)
- Silvery white metal, highly reactive
- Important for muscle contraction
- Inverse relationship with insulin
- Electrolyte—affected by ACE inhibitors, loop diuretics
Sodium (Na)
- Muscle contractions
- CNS stability, water balance
Titanium (Ti)
- Grayish metal
- Found in prosthetic implants—lightweight, low toxicity, high strength
Zinc (Zn)
- Bluish silver metal
- Calamine lotion, sunblock, wound healing, cold symptom relief
Molecular compounds are comprised only of ___
Nonmetals
Ionic compounds are almost always comprised of ___
A metal and a nonmetal
What are ionic compounds?
Sometimes referred to as salts—reaction of an acid with a base
What are polyatomic ions?
Formed when 2 or more nonmetal atoms are bonded together in a way that results in a net electrical charge
