2. Covalent Bonds

    ​    3. Hydrogen Bonds

   isotopes are variations of elements that have the same number of protons but different numbers of neutrons. 

    1. ionic bonds

  this sets up partially charged
​"poles" in the molecule.

clinical uses of radioisotopes

   nonpolar covalent bonds

An element's
​atomic number (#protons/# electrons)   is the number listed here at the upper left of each symbol. The atomic mass (#protons + # neutrons) is the number listed below the symbol.

   The pH scale measures how much H+ is in a solution.
A lot of Hydrogen = low pH # = an acidic solution = an acid
less H+ = a higher pH = a basic (alkaline) solution = a base

= partial charge

 General Chemistry

Carbon

 The outermost orbital shell of an atom is called its
​valence shell.
the electrons in the valence shell are valence electrons.

​Valence electrons are the highest energy electrons in an atom and are therefore the most reactive.

OH-
​ is a hydroxyl group

   It is important for cells/tissues maintain pH homeostasis.
The pH of the human body ranges between 7.35 to 7.45, with the average at 7.4  

Oxygen is more electronegative than H

         electrons are unevenly shared

 Carbon-14 
​is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons. Every 5,730 years, the radioactivity of carbon-14 decays by half which is called its half-life, a fact used during Carbon Dating.

Bonding:

atoms creating molecules

C and H have similar electronegativity

         electrons are evenly shared

is it just about H+?

    ​       pH

at pH 7
H+ and OH- concentrations are =

 Bases like NaOH containing OH- are considered strong because they also dissociate almost completely releasing OH-.
what does that do to the pH? 

 Electron orbitals 
 predict where an electron might be at any given time.   The number of orbitals increases as the atomic number increases. 

octet rule:
atoms tend to gain, lose, or share electrons in order to achieve a full outer electron shell with eight valence electrons ibn order to achieve a stable electron configuration.

   There can be strong or weak acids and bases

​Carbon (C) has an atomic number or 6 and an atomic mass of 12.01

   what do the pH numbers really mean?

Oxygen exhibits a partial negative charge  Hydrogen exhibits a partial positive charge. 

if one atom is highly electronegative and the other less electronegative, the covalent bond will be polar

Bonding Types:
​1. Ionic                    2. Covalent            3. Hydrogen

   isotopes

 Na (sodium) atomic number = 11

  Cl (chlorine) atomic number = 17  

pH 3  10*-3
​ has more H+ than pH 6  10*-6

in an aqueous solution,
​as H+ concentration increases, OH- concentration decreases.

   next up...
​biologically relevant molecules ;)

 diagnostics: 
 *techniques like PET scans and bone scans to visualize internal organs, tissues, and structures, aiding in the detection of tumors, infections, abnormalities.
 *tracer studies to track the movement and metabolism of isotope labelled molecules.
treatment: 
 * radiation therapy to deliver targeted doses of radiation to kill cancer cells and shrink tumors.
 * certain isotopes treat specific conditions like hyperthyroidism. isotopes are taken up by the thyroid gland and destroy overactive cells. 

HCl is a strong acid because it dissociates almost completely in water releasing H+. 
​
Acetic acid (CH3COOH = vinegar is 6% acetic acid) is a weak acid because it does not dissociate well in water.

 A solvent is a substance that dissolves  solute particles.
​  A solute is a substance that is dissolved by a solvent.

  properties of water

 Hydrogen bonds have about a tenth of the strength of an average covalent bond

polar covalent bonds
vs
non-polar covalent bonds

 hydrogen bonds are strong intermolecular forces created when a hydrogen atom bonded to an electronegative atom (polar covalent bond)  is attracted to a nearby electronegative atom. 

Hydrogen Bonds can only occur between two polar molecules. Why?

  polar covalent bonds