2.2- Molecular bonding Flashcards
When condensation reaction mean?
Reaction that occurs when two molecules are joined together with the removal of water.
What does hydrogen bond mean?
A weak interaction that can occur wherever molecules contain a slightly negatively charged atom bonded to a slightly positively charged hydrogen atom.
What does hydrolysis reaction mean?
Reaction that occurs when a molecule is split into two smaller molecules with the addition of water.
What does monomer mean?
A small molecule which binds to many other identical molecules to form a polymer
What does polymer mean?
A large molecule made from many smaller molecules called monomer.
What do atoms consist of?
-COVALENT BOND
Atoms consist of a nucleus (of proton and neutrons)surrounded by shells of electrons. Most atoms tend to be stable when their outer shell contains eight electrons. Atoms of different elements have different number of electrons in their outer shells. For example carbon has four electrons.
What is a covalent bond?
Sharing a pair of electrons between atom to gain a full outer shell and it becomes strongly bonded with the other atom.
How is a covalent bond drawn?
Drawn by a single line
Give an example of a covalent bond:
Because carbons outer shell is filled by four electrons, carbon forms four covalent bonds.
Hydrogen forms a single covalent bond
Oxygen two covalent bonds
Nitrogen three covalent bonds
What happens when condensation happen?
-condensation, hydrolysis and polymerisation
When condensation happens on your windows on a cold day, water vapour in the air has changed state and settled on the window as a liquid. The water vapour has been removed from the air.
WHat is a condensation and hydrolysis reaction?
A condensation reaction occurs when two molecules are joined together with the removal of water.
A hydrolysis reaction is when two molecules are split apart with the addition of water.
Almost all condensation reactions happen in the sae way, when two- OH groups react together. The reaction involves the breaking formation of bonds
What are condensation and hydrolysis reactions responsible for?
-MONOMERS AND POLYMERS
Condensation and hydrolysis reactions are involved for linking and splitting apart biological molecules in living things.
The units which are joined together are called monomers.
When two monomers join together they form dimers.
When lots of monomers join together they form polymers.
What do carbohydrates, lipids and protein contain?
All of these molecules contain carbon, hydrogen and oxygen atoms.
Proteins also contain nitrogen and sulphur and nucleic acids also contain nitrogen and phosphorus.
Lipids do not form polymers but they still contain ,C,H and O atoms
What type of molecule does carbohydrates have?
C,H and O
What type of monomer is carbohydrate?
Monosaccharides (glucose)
What type of polymer is carbohydrate?
Polysaccharides (starch)
What type of molecules does protein have?
C, H,O,N and S
What type of monomer is protein?
Amino acids
What type of polymer is protein?
Polypeptides and proteins
What type of molecules does nucleic acid have?
C,H,O,N and P
What type of monomer is nucleic acid?
Nucleotides
What type of polymer is nucleic acid?
DNA and RNA
What does water consist of?
-HYDROGEN BONDS
Water consists of two hydrogen atoms, each covalently bonded to one oxygen atom. However, because the oxygen atom has a greater number of positive protons in its nucleus, it exerts a stronger attraction for the shared electrons. This means the oxygen atom becomes slightly negative and the hydrogen atom becomes slightly positive . When this happens the water molecule becomes polar.
What is a hydrogen bond?
A hydrogen bond is a weak interaction which happen s whenever molecules contain a slightly negatively charged atom bonded to a slightly positive charge hydrogen atom
.The bond is a weaker than a covalent bond. However in some polymers thousands and thousands of hydrogen bonds form between chains of monomers. Having many bonds like this helps stabilise the structure of some biological molecules.
