Exam 1 Chapter 1 -2 Flashcards
Electrically insulating
Materials such as concrete, wood, and most plastics that don’t allow electricity to flow
Matter
Everything; Anything that occupies space and has a mass
Plasma
High energy charged particles similar to gas w/ no defined shape or volume but has good conductor of electricity and affect by magnetic fields ( lighting & neon signs)
Chemistry
The branch of science that focuses on the composition, structure, properties, and changes of matter
Atoms
Smallest unit of an element that can exit as a stable, independent entity
Molecule
A molecule is independent structure consisting of two or more atoms chemically bonded together. Can be compounds or elements
Scientific Notation
A system for writing numbers as the product of a number & 10 raised to the appropriate power
Nanotechnology
Manipulation of matter with at least 1 dimension sized between 1-100 nanometers where 1 nanometer (nm) =
Dimensional Analysis
The conversion of 1 unit from 1 form to another
Nucleus
A minuscule & high dense center composed of protons & neutrons
Electrons
Outside the nucleus of at atom that define the boundaries of an atom. Has a mass smaller than a proton or neutron
Atomic Number
The number of protons in the nucleus. The AN determines the identity of the atom. Found below the name & above the Chemical symbol (He has 2 protons, so has an atomic number of 2)
Mass Number
The number of protons and neutrons in the nucleus of the atom
Allotropes
Different elemental forms created from atoms of the same element
Rocks
Heterogenous solid-state mixtures that contain a variety of ionic compounds (minerals). Most complex mixtures of oxygen-containing minerals designated as oxides
Ore
A rock formation that contains a considerable concentration of a desired metal.
Metallurgy
The process of extracting & purifying metals from ore
Transistors
Billions are in computer chips and used to perform the operations needed by tech devices
Quartz
Pure crystallized silicon dioxide, a clear and colorless mineral that is the primary component of sand
Amorphous disordered material
A solid in which the constituent atoms, ions, or molecules are arranged in a random, disordered array
Silica
Naturally occurring substance that has a well-ordered structure composed of repeating linkage between Si and O. Often clear and colorless (quartz)
1ppm
1 part per million, while 1% is 1 part per hundred. 100/1,000,000 = 10,000, so 1 ppm is 10,000 times smaller than 1%.
ppm scientifc notation
ppb scientifc notation
ppt scientifc notation
Diatomic molecules
molecules composed of only two atoms, of the same or different chemical elements
With Significant figures all non-zero digits are
1.55 g has ____ SF
Significant 1.55 g = 3 sig. figures
With Significant figures all zeras embedded between non-zero digits are
1.003 mL has ____ SF
Significant. 1.003 mL has 4 SF
With Significant figures all trailing zeros are
1.000 g has ____ SF
Significant. 1.000 g has 4 SF
With Significant figures leading zeros are
0.00305 mL has ____ SF
not significant. 0.00305 mL has 3 SF
With Significant figures adding or substraction answer is based on
1.003 g + 0.2 g + 0.001 g =
smallest number decimal places.
* 1.003 = thousandths
* 0.2 = tenths
* 0.001= thousandths
so 1.003 g + 0.2 g + 0.001 g = 1.2 g to the tenths
With Significant figures Multiplication or division answers based on
1.002 cm x 0.005 cm =
Smallest number of Sig. Figs.
* 1.002 cm = 4 SF
* 0.005 cm = 1 SF
1.002 cm x 0.005 cm = 0.005 (1 SF)
Touchscreens respond only to
electrically conductive objects (like our bodies)
The properties of a device are governed by
what it’s made of (Matter)
What Phases of matter are found on Earth
Solid, Liquids, and Gases
Properties of solid
- Take shape of container =
- Fill Container =
- Definite Volume =
- Definite Shape =
- Take shape of container = No
- Fill Container = No
- Definite Volume = Yes
- Definite Shape = Yes
Properties of Liquid
- Take shape of container =
- Fill Container =
- Definite Volume =
- Definite Shape =
- Take shape of container = Yes
- Fill Container = No
- Definite Volume = Yes
- Definite Shape = No
Properties of Gas
- Take shape of container =
- Fill Container =
- Definite Volume =
- Definite Shape =
- Take shape of container = Yes
- Fill Container = Yes
- Definite Volume = No
- Definite Shape = No
Properties of Plasma
- Definite Volume =
- Definite Shape =
- Definite Volume = No
- Definite Shape =No
States of Matter can be either
pure substances or mixtures.
Mixtures
mixing of several pure substances
Homogenous Mixture / Solution
Uniform mix of pure substances (salt water)
Heterogenous Mixture
Un-Uniform mix of pure substances (sand & water)
Pure Substances
Composed of a single substance made up of atoms
Element
Something made of one type of several atoms (copper)
Elements are named for properties, planets, places, & people
Compounds
A substance that can be broken down into two or more simpler substances by chemical methods.
Chemical Formula
Symbolic way to represent the elementary composition of a substance. Reveals the elements present (chemical symbol/ atomic symbols) and the atomic ratio of element (subscripts)
Background on Periodic Table
- Periodic table *developed by Dimitri Mendeleev *
- Periodic table elements are arranged based on similarities in reactivates and properties.
- 90 elements occur naturally on Earth & others through synthetic nuclear reactions (Plutonium)
- Elements listed by numbers
Color Code of Periodic Table
Pink = metals ( most of table)
Blue = Non-metals (gases, liquids, or solids)
Green = Metalloids [8] (between metals & nonmetals)
Features of Pink elements on Periodic table
Solid at room temp, shiny, permanently deformed w/o breaking or cracking, effective conductor of electricity & heat
Features of Blue elements on Periodic table
Poor conductivity of heat or electricity, solids can’t be deformed w/o cracking or breaking.
Features of Green elements on periodic table
Semimetals/semiconductors
Columns of the period table are called ____ Organized by
- groups
- important properties they have in common, numbered from left to right.
Group 1 & 2 far left of period table
alkali metals & alkaline earth metals
Group 17
Halogens (fluorine & chlorine)
Group 18
noble gases ( helium & Radon)
Elements that have been discovered vs. compounds that have been isolated, identified, and characterized
118 elements vs 20 million compounds
Atoms can be split using
high-energy reactions.
X-ray light waves are
used to see atoms
The center of an atom is called a
Nucleus
The nucleus contains
protons and neutrons
Protons
positively charged particles
Relative Charge: +1, Relative mass: 1, Actual Mass 1.67 x 10^-27
Neutrons
electrically neutral particles
Relative Charge: 0, Relative mass: 1, Actual Mass 1.67 x 10^-27
Outside the nucleus are
electrons - negatively charged particles
Relative Charge: -1, Relative mass: 0, Actual Mass 9.11 x 10^-31
In a neutral atom number of protons =
number of electrons
How to determine the number of protons, electrons, and neutrons in an element:
- Protons: the atomic number
- Electrons: the atomic number - Mass Number
- Neutrons: Mass Number - Number of Protons
The electrical conductivity of materials depends on
their 3-D structure & mobility of electrons
the easier an electron can move to another atom = more conductive
80% of the 118 elements in the periodic table
are metals
Metals in portable electronics
aluminum, copper, nickel, lithium, tin & lead
Most metals in the periodic table are
not found on Earth as pure metals
Many elements (Al) react to
oxygen to form chemically stable compounds
Al & other metallic elements are found
in rocks
If it costs more than $100 million to mine & process the deposit, it’s a
rock not an ore
Elemental composition of the minerals comprising Earth’s Crust
- 47% O, 28% Si, 11% Group 1-2, 8% Al, & 5% Fe
- Oxygen + silicon in minerals = silicates
- Aluminum + oxygen = aluminates
- Silicon + Aluminum + Oxygen = aluminosilicate
Metallurgy process
- Metal extracted & concentrated from the ore through grinding & leaching
- High-temperature chemical reactions isolate the metal from its ore
Tin & Lead require lower heat
Computer chips “Heart of our electronics”
made of silicon (Si), microprocessor (9N/0.001 ppm/1 pub purity)
Silicon
doesn’t exist on Earth as a pure element; it’s formed as a compound SiO2 (silica)
Sand to silicon
- Sand reacted with Carbon to produce Silicon (purity of 95-98%)
- Clean rooms are used to process the resulting 9N purity
The largest component of Earth’s crust is
silica (silicon dioxide ) SiO2
Atomic-level of silica
repeating linkages between silicon & oxygen in a dense spiderweb-like structure
Atomic structure of glass
random array of silicon and oxygen linkages throughout solid
From sand to glass
heating sand to its melting point, then cooling until it hardens to glass
Three pillars of sustainability
- Environmental - pollution prevention, natural resource use
- Social - better quality of life for all members of society
- Economic - fair distribution and efficient allocation of resources
Materials comprising a cell phone
40% metals, 40% plastics, 20% ceramics & glass
Form the focus of the “cradle-to-grave” approach to consumer goods
- Energy consumed to produce goods
- Waste products created when goods are made
- Raw materials from which goods are made
Rare earth metals are used for
- Vehicle catalytic converters
- Fluorescent lighting
- Memory chips
- Rechargeable batteries
- Magnets
- Speakers
- Advanced Weaponary
Most of the world’s supply of rare earth metals is controlled by
China
Environmental challenges to extracting metals from recycled electronic devices
- Solvents used to remove the plastic are not environmentally friendly
- Groundwater could be contaminated with heavy metals
- Contaminated groundwater could contribute to an increase of cancers in surrounding communities
Finding the charge of ionic compounds
Respiration
The process of taking in Oxygen to help metabolize the foods we eat to produce Carbon Dioxide and water and to release the energy that powers other chemical reactions in our bodies
Air
A collection of gases mixed together in various proportions, is classified as matter
Troposphere
Lowest layer of the atmosphere where we live; accounts for 75% of mass of entire atmosphere
Stratosphere
Second lowest layer (between Troposphere and Mesosphere) of the atmosphere where the Ozone Layer is
Mesosphere
Third lowest layer ( between Stratosphere & Thermosphere) of the atmosphere where shooting stars burn
Thermosphere
Second highest layer ( between Mesosphere & Exosphere) of the atmosphere which has large temperature fluctuations
Exosphere
Highest layer of the atmosphere
Percent
Parts per hundred