Transcript SNC1d1 chemistry
SNC1D1 CHEMISTRY
Extra bits
Oxygen is necessary for combustion to occur. A test for oxygen is to see if a glowing wood splint will ignite.
Hydrogen is an explosive gas.
A test for hydrogen is to put a burning splint in the gas and it will pop. (Pop test) Carbon dioxide reacts with limewater to produce a milky white mixture (precipitate formed – solid formed) when you blow into it with a straw.
A test for carbon dioxide is that if you blow the gas into limewater: you will cause it it turn milky white.
GAS TESTS
http://www.youtube.com/watch?v=LiAvDpl5aJA
The electron is the smallest particle with a mass of 9.11 x 10 -31 kg.
The proton is the next largest with a mass of 1.673 x 10 -27 kg.
The neutron is the largest mass of 1.675 x 10 -27 kg.
Note: the mass of a neutron is about the same as the mass of a proton (slightly larger).
Note: the electron’s mass is so small, that losing electrons has a negligible effect on the mass of the atom (forming ions)
MASSES OF SUB-ATOMIC PARTICLES
If we assume that a neutron has a mass of 1, then the relative masses are: Neutron = 1 Proton = 0.99862349
Electron = 0.00054386734
Said another way, protons are only about 99.86% as massive as neutrons while electrons are only about 0.054% as massive as neutrons. While relative masses are nice if you want to compare protons, neutrons and electrons to one another, it doesn't tell you what the actual masses of these particles are. In kilograms, the masses are: Neutron = 1.6749286*10 -27 Proton = 1.6726231*10 -27 Electron = 9.1093897*10 -31 kg kg kg
MASSES OF SUB-ATOMIC PARTICLES
A compound is a pure substance that can be broken down into two or more elements.
A compound is a pure substance composed of two or more different elements that are chemically joined. (page 211) Table salt NaCl is a compound made from sodium and chlorine.
An element is a pure substance that cannot be broken down into a simpler chemical substance by any physical or chemical means. (page 211)
ELEMENTS AND COMPOUNDS
Given a substance, you should be able to list some chemical and physical properties of it.
Ex) Iron is a solid metal, a good conductor, greyish-red in colour, reacts with oxygen to create rust and is magnetic.
Water:
PHYSICAL AND CHEMICAL PROPERTIES
Alkali metals all have a valence electron of one. (Group 1) Alkali metals all give up one electron to become stable as a cation.
Alkali metals react readily with halogens to form ionic compounds.
Alkali metals all react vigorously with water. (reactivity increases going down the group) Alkali metals all have metallic properties.
PHYSICAL PROPERTIES OF GROUPS
Halogens all have 7 valence electrons. (Group 7) Halogens all take one electron to become stable as an anion.
Halogens react readily with alkali metals to form ionic compounds.
Fluorine is the most reactive halogen, so reactivity increases going up the group.
Halogens are all non-metals.
PHYSICAL PROPERTIES OF GROUPS
Noble gases all are stable as outer shell is full. (No electrons needed to be gained or lost).
Noble gases do not react chemically with anything, unless forced to.
Used for lights like neon – produces red, Krypton – produces purple, etc.
PHYSICAL PROPERTIES OF GROUPS
H 2 is hydrogen gas CO 2 is carbon dioxide.
H 2 O is water.
O 2 is oxygen gas.
CH 4 is methane.
NaCl is table salt.
C 6 H 12 O 6 is glucose.
C 12 H 22 O 11 is table sugar.