form 4 chapter 2
TRANSCRIPT
Chapter 2 Matter
Atoms• Smallest particle of an element
Molecules• Two or more atoms bonded together
COVALENTLY
Ion
• Positively charged or negatively charged
Elements• Consists of only one atoms
Sulphur is an element !
• Consists of ALL the same ATOMS • All S atoms
How do we know ?• Atomic Force Microscopy (AFM)
Diamond • Consists of ALL the same ATOMS • All C atoms
Compounds
• Consists of only two or more different atoms BONDED CHEMICALLY TOGETHER
Sodium Chloride (NaCl)
How do we know ?• Surface Electron Tunneling Microscope
• NaCl a compound !
Sulphur hexafluoride• Contains S and F
NanoKids
FAME !!
Kinetic Theory of Matter
State Solid Liquid Gas
Arrangement
Movement Vibrate and Rotate and FIXED position
Packed closely but no in order
Very far from one another in random arrangement
Forces of Attraction Strong Medium Weak
Energy Content Low Medium High
Rates of Diffusion
Napthalene• Has Van Der Waals attraction
A to B• Solid temperature increase
B to C
• Energy absorbed used to break bonds• Breaking bonds needs ENERGY !
C to D• Liquid temperature increase
D to E• Boiling !!!
E to F• Gas temperature increase
• Bond formation needs energy !
Bond breaking: Absorb EnergyBond formation: Release Energy
Bond formation
Bond formationReleases
Heat into water
BUT….Water
ReleasesHeat into surroundings