Week 1 Lecture: Elements and the Periodic Table Flashcards
What is chemistry concerned with?
The composition and transformation of matter.
What are the levels of organisation in the human body?
Chemical level, cellular level, tissue level, organ level, organ system level, organism level.
What is the definition of matter?
It has mass and occupies space.
What does mass include?
All things living and non living.
What are the three physical states of matter?
Solid, liquid and gas.
What does the state of matter depend on?
Temperature, surrounding pressure and the forces holding its structural particles together.
What does whether it’s a pure substance or mixture refer to?
It’s composition.
What is a pure substance?
It has a fixed composition.
Are pure substances hard to break down?
Yes.
What are the two types of pure susbstances?
Elements and compounds.
What is an element?
An element contains one type of material.
What is a compound?
A compound consist of two or more types of material in a distinct ratio.
What is a mixture?
Composition can vary. They are not chemically bonded and can be separated into pure substances.
What are the two types of mixtures?
Homogenous and heterogenous.
What is a homogenous mixture?
It has one phase and looks all the same.
What is a heterogenous mixture?
Two phases.
What are the ways of separating mixture?
The ways of separating mixture include filtration and chromatography.
How many elements have been discovered and isolated?
117
How many elements occur naturally?
88
What are the four things chemicals are named after?
Geographical, planets, Greek/Latin words, famous people.
What are is the chemical system?
One letter symbol, two letter symbols, two letter symbols (non English names).
What is the periodic table?
A flowchart of how chemicals are grouped together.
What is groups?
Down.
What are periods?
Across.
