Liceo Classico “L. Ariosto”Ferrara

Chemistry course

CHNOPS: the six elements of life

Teacher

Maria Petresi

The four major types of macromolecules found in

living cellsMacromolecules

Elements Monomer Polymer Example

Carbohydrates C, H, O Simple sugar

Polysaccharides

Starch

Lipids C, H, O Fatty acids & glycerol

Lipids Fats, oils, waxes

Proteins C, H, N, O, S

Amino acids Polypeptides Insulin

Nucleic acids C, H, O, P Nucleotides Nucleic acids DNA

Elements: where?

•Organisms:C,H,N,O,P & S …

“CHNOPS”

•Earth’s crust:

O,Si,Al,Fe …

•Universe:

H,(He),O,C,(Ne),N,Mg,Si,

Fe,S …

The setting of CHNOPS in the periodic table of elements

Group and period identification of CHNOPS

Homo sapiens’

atomic

composition

Human

CHNOPS in…

CHNOPS in…

Escherichia coli’s

atomic

composition

Bacterium

CHNOPS in…

Poa pratensis’

atomic

composition

Plants

•Symbol: C

•Group: 4th

•Period: 2nd

•Atomic number: 6

•Atomic mass number: 12

•Valence: 4

•Electrons number: 6

Carbon

6

C

12.00

What?

•Non-metal

•It’s solid at room temperature

Where?

•In all fondamental composts of living things

•Atmosphere (CO2)

•Earth’s crust

Why?

•There aren’t living things without carbon

•Symbol: H

•Group: 1st

•Period: 1st

•Atomic number: 1

•Atomic mass number: 1

•Valence: 1

•Electrons number: 1

Hydrogen

1

H

1.008

What?

•Non-metal

•It’s gas at room temperature; H2

•An element apart

Where?

•The most common in the Universe.

Why?

•In many inorganic compounds (H2O, hydrides, hydroxides and acids)

•In organic compounds

Nitrogen7

N

14.01

•Symbol: N

•Group: 5th

•Period:2nd

•Atomic number: 7

•Atomic mass: 14

•Valence: 3

•Electrons number: 7

What?

•Non-metal

•It’s gas at room temperature; N2

Where?

•It’s the most common in the atmosphere

•In all living organisms

•In proteins

Why?

•It can form many compounds with oxygen.

Oxygen8

O

16.00

•Symbol: O

•Group: 6th

•Period:2nd

•Atomic number: 8

•Atomic mass: 16

•Valence: 2

•Electrons number: 8

What?

•Non-metal

•It’s gas at room temperature; O2

Where?

•It’s the most common in the Earth’s crust

•In the atmosphere: 21%

•In all living organisms (biomolecules)

Why?

•It’s foundamental to all living organisms (cellular respiration, photosynthesis……)

Phosphorous

15

P

30.97

•Valence: 5

•Electrons number: 15

•Symbol: P

•Group: 5th

•Period:3rd

•Atomic number: 15

•Atomic mass: 30

•Valence: 5

•Electrons number: 15

What?

•Non-metal

•It’s solid at room temperature; P4 (white phosphorus)

Where?

•In nature it appears as a calcium phosphate

•In the skeletons of animals

•In ATP; in the nucleic acids (PO43-)

Why?

•It forms only single bonds

Sulfur

16

S

32.07

•Symbol: S

•Group: 6th

•Period:3rd

•Atomic number: 16

•Atomic mass: 32

•Valence: 2, 4, 6

•Electrons number: 16

What?

•Non-metal

•It’s solid at room temperature; S8 (rhombic sulfur)

Where?

•In nature it’s in volcanic areas

•In minerals

•In the proteins

Why?

•It can form 2, 4 or 6 bonds

The Lewis configuration

CHNOPS valence

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