Chemistry
Physical Property: A physical property is one that is displayed without any change in composition
Chemical Property: Any characteristic that gives a sample of matter the ability/inability to undergo a change that alters its composition. Examples: Alkali metals react with water; Paper's ability to burn.
Physical Change: Change in which the matter's physical appearance is altered, but composition remains unchanged. (Change in state of matter)
Chemical Change: Change in which one or more kinds of matter are transformed to new kinds of matter with altered compositions (or Chemical Reaction).
1. Change of color
2. Formation of gas
3. Formation of precipitate
4. Change of temperature
5. Energy produced
Corrosion works over very long time periods until the source material is depleted, combustion has to be a fast reaction otherwise the fire goes out and the process reverts to one more like that seen in corrosion.
1. Matter is made up of tiny particles (Atoms & Molecules)
2. Particles of Matter are in constant motion.
3. Particles of Matter are held together by very strong electric forces
4. There are empty spaces between the particles of matter that are very large compared to the particles themselves.
5. Each substance has unique particles that are different from the particles of other substances
6. Temperature affects the speed of the particles. The higher the temperature, the faster the speed of the particles.
A pure substance is any single type of material. hydrogen - 'squeaky pop' test - if there is a pop H2 is present oxygen –
Put a glowing splint into possible source, oxygen will re-ignite it
CO2 - Add CO2 into lime water and if CO2 is present it will turn milky
Neutral Atom has a 0 charge (same protons and electrons)
An ion is when the atom has a charge, imbalance of protons (+) and electrons (-) (usually +1 or -1)
Excited atom is when and electron on an atom is in an excited state (when it jumps energy levels when you put energy into it)
Ions are electrically charged particles formed when atoms lose or gain electrons. They have the same electronic structures as noble gases. Metal atoms form positive ions, while non-metal atoms form negative ions.
Calculate density by D=M/V
1 atom – “Mono-“
2 atoms – “Di-“
3 atoms – “Tri-“
4 atoms – “Tetra-“
5 atoms – “Penta-“
6 atoms – “Hexa-“
7 atoms – “Hepta-“
8 atoms – “Octa-“
Crisscross method used for all compounds
Ionic compounds involve ions, so they are typically the combination of a metal and a non-metal
Molecular compounds always involve two non-metals
Electricity
Induction is a charged object to a neutral object without touching
Friction is rubbing so electrons transfer
Conduction is a charged object to a neutral by