Lifestyle Chemistry Flashcards
(21 cards)
What is a colloid?
A mixture containing particles that remain suspended for long periods of time
What is a solution?
A homogenous mixture that contains a solvent and a solute
What is a suspension?
A heterogenous mixture that contains big particles and forms layers quickly
What are constituents?
Is the components that make up of materials and substances
What is surface tension?
The forces that is experienced by particles on a liquid’s surface
What are cohesive forces?
Cohesive forces are the attraction forces between particles
What are adhesive forces?
Adhesive forces are experienced between particles and another substance
I.e. Solids and liquids
What does a surfactant do?
Reduces surface tension
What is does an emulsifier do?
Allows immiscible substances in a liquid that do not normally mix to mix and stay mixed
What is an emulsion?
An emulsion is a liquid of two substances that don’t mix
What is interface?
The meeting point of two substances
What is the difference between surfactants and emulsifiers?
Emulsifiers are a class of surfactants whilst surfactants are materials that interact at the surface
What is cationic?
An ion with a positive charge
What is anionic?
An ion with a negative charge
What are the characteristics of the term lipophilic?
- Oil loving and non-polar
- Attracted to grease and oil
What is the characteristics of the term hydrophilic?
- Water loving
- Attracted to water molecules
2.4 - Explain why cleaning agents must be surfactants and emulsifiers
- Surfactants: Because they interact at the interface between two immiscible substances creating an emulsion
- Emulsifiers: Because they maintain the emulsion
What is biodegradable?
A substance that can be broken down by living organisms such as microbes
What are the three main layers of the skin?
- Epidermis, the outer layer
- Dermis
- Subcutaneous tissue, the underlying fatty material
What are the functions of the skin?
- Protects the body from the external environment
- Assists with temperature regulation
- Protects against entry by disease-causing organisms
Define the term microflora
Refers to bacteria, fungi, algae, protozoa and viruses
