Nanoparticles

Question 1

What are nanoparticles

Answer 1

Particles which are smaller than 100 nanometres across.

Question 2

What do nanoparticles naturally occur in?

Answer 2

Smoke and fried food

Question 3

Uses of nanoparticles

Answer 3

Used to strengthen the rubber in tyres

Give black inks and leather their colour

In solar cells - very high surface area - absorbs more sunlight

Also have high electricity conductivity, replace silicon crystals

Question 4

Possible problems with nanoparticles?

Answer 4

Concerns ‘free’ nanometres could enter into the liver and brain. Leading to similar effects to asbestos on the body.
It also is not known how they behave in water or soil - could cause damage to the environment.

Question 5

Size of a nanoparticule?

Answer 5

Between 1-100nm in size and contains a few hundred atoms

(1X10(-9)m or 0.000000001m)

Question 6

Different properties of nanoparticles compared to bulk materials ?

Answer 6

The tiny size of nanoparticles compared to bulk materials

A large surface area to volume ratio

Question 7

Advantages of nanoparticles in sunscreen

Answer 7

They give better skin coverage to the sunscreen
They give more effective protection from the sun’s ultraviolet rays
They are clear and colourless, makes cream invisible on skin
They not degrade on exposure to the sun

Question 8

Disadvantages of nanoparticles in sunscreen

Answer 8

Potential cell damage in the body- so small, may be able to penetrate cell membranes, or be breathed in.

They may be more reactive/toxic than the bulk materials.

Harmful effects on the environment