Periodic Table of Elements

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  • 1869
  • Dmitry Mendeleev 
  • all of the elements know to man arranged due to their chemical processes 
  • in order by atomic number 
  • each vertical column behave in similar ways 
    • far right column is all inert elements; their atoms do not interact with other elements. 
    • in nature these elements only exist as solitary atoms. 
    • Far right column--noble gases; can't bond with anything else

Atomic Number 

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  • The number of protons in the nucleus. 

4 Things Nobody Knows...

•  
  • Weak Nuclear Force 
    • how do the electrons not attack the nucleus?
  • Gravity 
    • how does it work?
  • Magnetism 
    • how does it work? 

Atomic Weight (Mass) 

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  • protons + neutrons = amotic mass 
  • the mass number of an isotope is shown as superscript to the left of an element’s symbol 
  • the most common is ^12 C; 6 protons, 6 neutrons 

Isotopes

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  • all elements occur in different forms called..... 
  • refer to isotopes by mass number 

Radioisotopes

•  
  • radioactive isotopes 

Radioactive Decay

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  • can transform one element into another 
  • ex. 
    • ^14C is a radioisotope of carbon

Tracer

•  
  • any molecule with a detectable substance attached. 
  • typically, a radioactive tracer is a molecule in which radioisotopes have been swapped for one or more atoms. 

Shells and Electron 

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  • Shell Model 
    • helps to check an atom for vacancies 
    • Electron placement affects the way atoms are arranged and attach 
      • if the outside orbital is not fully filled it will bond in 1 of 3 ways. 
        • valence
        • ionic
        • covalent
          •  
    • with this model, nested “shells” correspond to successive energy levels.
      • 2->8->8

electrons can leap to high energy levels and fall back down, creating a chemical spark of light 

can also jump between atoms

atom that carries a charge because of an unequal number of protons and electrons 

(more protons)

Can never raise above 212⁰f 

Is a temperature stabilizer 

Solid is less dense than liquid

in PURE water some molecules form H(+) + OH(-) 

hydroxel group 

L> hydrogen ion   

pH 7 -> neutral 

-7 -> acidic

+7 -> base

*acids and bases burn in the same way

molecules that bind to hydrogen,or release hydrogen, to neutralize acidity

checks acidity in the blood stream

acts like sponges

Stable 

all life has to be carbon based 

Hydroxel

Carboxel

Amino 

Phosphate

use plant's glucose molecules as sugar for us 

*sugars come in simple molecules as well as chains 

monosaccharides- 3 to 7 atoms

CHO --> always 1:2:1 ratio (sugars)

Fructose

Glucose

Sucrose

Come in simple molecules as well as chains.