Chem final Flashcards
1-2 letter abbreviations for elements
Most are straightforward (O = oxygen, Si = Silicon, etc)
Elements based on Latin or Greek names
-Pb = Lead
-Hg = Mercury
-Cu = Copper
-Fe = Iron
=K = Potassium
-Sb = Antimony
-Ag = Silver
Au = Gold
All matter: Mixtures
- If the matter can be separated by a physical process then it is a mixture.
- If the matter can not be separated by a physical process it is not a mixture
All matter: Compounds or elemnets
- If the matter is not separated by a physical process it turns into a pure substance.
- If the substance can be broken down into simpler ones by chemical means, then it is a compound.
- If it can not be broken down into simpler ones by chemical means then it is an element
Classification of matter
- The four components of matter are solids, liquids, gases, and plasmas
- Matter can be divided into pure substances and mixtures.
- Pure substances may be elements (containing atoms of the same type–for instance, silicon (Si) or compounds (containing 2 or more different types of atoms–for example, silicon dioxide (SiO2)
- Mixtures may be heterogeneous (with a composition that caries throughout, such as gravel) or homogeneous (with a unifrm composition throughout, such as solutions of sugar dissolved in water)
Molecule
- A space-filling model for a water molecule is H2). There’s two hydrogen atoms, and one oxygen atom.
- A molecule is a fixed number of atoms held together by chemical bonds in certain spatial arrangement .
- The chemical formula symbolically represents the type and number of each element present
Classifying matter: Compounds
- Carbon dioxide
- Cocaine.
- Water
- Table salt
Classifying matter: Element
- Nickel.
- Fluorine
Classifying matter: Mixture
- Soap.
- Sea water
Atoms: Compounds
- Ionic compounds are composed of oppositely charged ions. Electrons are either added or subtracted from atoms to form ions.
- Molecular compounds are composed of molecules, which ate made up of atoms.
- The four states of matter, elements, compounds, and mixtures are on the macroscopic scale (can view with the naked eye), individual molecules, ions, and atoms are on the sub-microscopic or nanoscale (one-billionth of a meter)
Example: Different compounds containing the same element will have different physical and chemical properties
- Fe: Magnetic
- Fe2O3: Non magnetic
Properties of subatomic particles: Prton
- Relative charge: +1
- Relative mass: 1
- Actual mas, kg: 1.67 x 10^-27
Properties of subatomic particles: Neutron
-Relative charge: 0
-Relative mass: 1
Actual mass, kg: 1.67 x 10^-27
Properties of subatomic particles: Electron
- Relative charge: -1
- Relative mass: 0**
- Actual mass, kg: 9.11 x 10^-31
**0
This value is zero when rounded to the nearest whole number. it does have a mass, though it’ve very small
Properties of subatomic particle
- Most of the mass in an atom is found in the nucleus.
- Protons and neutrons are found in the nucleus.
- Electrons are located outside the nucleus
Atomic number (Z)
the number of protons (nuclear charge)
Mass number (A)
The sum of the protons and neutrons
Electrical conductivity
- Metals are electrically and thermally conductive.
- Electrical conductivity involves the movment of electrons through the 3-D structure of a conductor
Cu
- Atomic number = 29
- Therefore ti contains 29 protons (29+ charge).
- To balance the charge, it contains 29 lectrons (29 - charge).
- Mass number = number of protons + number of neutrons (0 charge)
- Number of neutrons = 63 -29 = 34