3.2 Water

What is a polar molecule?

A polar molecule is when the electrons shared in a covalent bond spend more time closer to one atom than the other, thus creating polarity and delta charges because the atom where the electrons spend more time with will become slightly negative and the one neglected will become slightly positive.

What atoms are in a water molecule?

2 Hydrogen and one oxygen

Is Water a Polar Molecule?

yes

In a Polar water molecule, where do they electrons spend the most time?

Around the oxygen atom

Why are the electrons slightly attracted to the oxygen atom in a water molecule

Because even though they’re re neutralised, oxygen has 8 protons and Hydrogen only has 1

What is a delta charge in a polar molecule?

A delta charge is created in a polar molecule, it isn’t fully charged, just a little :)

What type of bond does a Delta charge create in a water molecule?

It creates a hydrogen bond between the delta positive hydrogen and the delta negative oxygen

Which property of water creates insulation allowing for a stable habitat for water organisms in the winter?

Water freezes at 0 Celsius and ice is less dense than water

Which property of water allows for the transport of nutrients etc throughout the body and in plants without evaporation?

Water is thermostable

which property of water causes water molecules to stick together, allows for water to be drunk through a straw or for an insect to be able to walk on the surface?

tension and cohesion

Which property of water causes capillary action, causes water to stick to charged surfaces?

Adhesion

What is electronegativity

The tendency of an atom to attract elextrons, creating delta charges.

is glucose polar

yes

is HCL polar

yes

is oxygen polar

no

is hydrogen polar

no

5 functions of H2O

Solvent, Transport medium, Chemical reaction medium, Coolant, Habitat.

Explain how H2O can be used as a solvent

can dissolve polar molecules like enzymes glucose and amino acids.

How can water be used as a medium for chemical reactions

For chemical reactions to occur the molecules have to be able to travel freely across a distance in order to come into close proximity to react. Water allows this through weak H bonds, that can constantly reconnect.

how can water act as a coolant

through sweat, the water evaporates, removing heat on the skin through Kinetic Energy transfer. This prevents our enzymes from denaturing.

How can water act as a transport medium in animals

blood plasma is bade up of mostly water, and makes up 55 percent of our blood.

How can water act as a transport medium for plants

phloem: Transports dissolved sugars and assimilates.
Ploem, transports water through capillary action, caused by adhesion and cohesion.