background preloader


Facebook Twitter

How to visualize one part per million - Kim Preshoff + The TED-Ed Community. What is measured in parts per million, parts per billion, or parts per trillion? Take a look at some concentration analogies here. Commonly, substances thought of as contaminants or toxins such a PCB’s, lead, mercury, and pesticides, are measured in these small concentrations. Need a bit more about exactly what is meant by a ppm or ppb? This article will provide you with some more examples and explanations, as will what does ppm or ppb mean? If you think parts per million is small, try imagining parts per billion.

Parts per billion is a common measurement used for toxins in drinking water such as lead and mercury. Climate change is another topic where the term “parts per million” is discussed. Have trouble understanding large numbers? Another way to increase your understanding is to scale things down. Ginormous Numbers Could Create a Mental Black Hole also gives some insight into the difficulty of large numbers to the human brain. GCSE Bitesize Science - Making ammonia : Revision. Lithium-ion batteries: How do they work? How batteries work - Adam Jacobson. Several advancements soon followed the Voltaic pile.

British chemist John Frederic Daniell replaced the salt water with a solution of copper sulfate, which would be reduced into pure copper on the surface of the copper. The copper was no longer a flat plate, but a copper pot that held the solution, a zinc rod, and a porous earthenware pot separating them. The Daniell cell could generate up to 1.1 Volts without the hydrogen gas problem, a vast improvement on Volta’s short-living pile that measured only 0.8 volts. French Scientist Georges Leclanché improved on this in 1866 – he switched out the copper and copper sulfate for a carbon rod sitting in a solution containing manganese IV oxide, which would reduce to manganese (III) oxide.

This upped the voltage to 1.4 Volts and found a lot of usage powering telegraphs and early telephones. This “battery,” however, was still a glass jar full of nasty chemical solutions. 300 years of fossil fuels in 300 seconds. Uses of Polymers - EasyChem - The Ultimate Resource for HSC Chemistry: Syllabus-Based Dot-Point Study Notes/Summaries, Past Exam Papers, and More. Plastics and Polymers. From DNA to Silly Putty, the diverse world of polymers - Jan Mattingly. Muscle fibers, DNA and plastics are all examples of polymers. Watch this video to learn more. Check out Macrogalleria, where you can learn all kinds of nifty stuff about polymers and polymer science!

A sustainable polymer is a plastic material that addresses the needs of consumers without damaging our environment, health, and economy. The feedstocks for sustainable plastics are renewable, such as plants. The production of sustainable polymers should use less net water and non-renewable energy, emit less greenhouse gases and have a smaller carbon-footprint than their non-sustainable counterparts, while still being economically viable. Because everything that we see and use every day is made up of natural or synthetic (man-made) polymers, it’s important to know how they are created, how they can be used, and how they affect our lives. 10B1 give us the lowdown on how different additives affect the properties of polymers. 10 Polymer-based Products You Use Every Day Is it a solid?

Polymerization. Animation of a Radical Polymerization. Animation of a Condensation Polymerization. IGCSE Chemistry: Condensation Polymerisation-Nylon. Note: This is for SINGLE SCIENCE. How to make nylon: (he uses a diamine which is one of the monomers, but doesn't use a dicarboxylic acid so just beware of that. the video's just essentially to show you what it looks like to make nylon, stuff about the monomers are below) Reviewing addition polymerisation vs. condensation polymerisation.

This is a really good video to show you the difference and to explain it. It may not be about nylon, but the concept is essentially the same and it also loses a water molecule in the process, which is the same as when nylon is produced. 5.17 recall that nylon is a condensation polymer 5.18 understand that the formation of a condensation polymer is accompanied by the release of a small molecule such as water or hydrogen chloride Condensation polymers are basically polymers formed through a condensation reaction, where the monomers react and a polymer is produced, and a small molecule such as water is also produced as a by-product of the reaction.

Basic Chemistry: Atoms and Ions. Atoms Atoms are the basic unit of chemistry. They consist of 3 smaller things: Protons - these are positively charged (+) Electrons - these are negatively charged (-) Neutrons - these have no charge These 3 smaller particles are arranged in a particular way. In the center is the Nucleus where you find the positive Protons and neutral Neutrons. In orbit around the nucleus are the Electrons. Interaction of AtomsIt's the electrons in orbit around the nucleus that allow one atom to interact with other atoms so they can be linked together. Ions Sometimes atoms gain or lose electrons. Positive Ion - Occurs when an atom loses an electron (negative charge) it has more protons than electrons. The following image shows Na losing an electron and Cl gaining an electron Thus the Na becomes Na+ The Cl becomes Cl- How batteries work - Adam Jacobson. How batteries work - Adam Jacobson | TED-Ed. University of Nottingham.


These are giant molecular lattice structures. This implies that strong covalent bonding holds their atoms together in a highly regular extended network. The bonding between the atoms goes on and on in three dimensions. Melting requires the separation of the species comprising the soild state, and boiling the separation of the species comprising the liquid state. Because of the large amount of energy needed to break huge numbers of covalent bonds, all giant covalent network structures have high melting points and boiling points and are insoluble in water. Diamond, graphite (allotropes of carbon) and quartz (silicon(IV) oxide, SiO2) are examples. Diamond and Graphite Diamond and graphite are crystalline forms of the element carbon. In graphite each carbon atom is covalently bonded to three others in the same plane.

In diamond all four outer electrons of each carbon atom are 'localised' between the atoms in covalent bonding. Other forms of carbon, such as charcoal, are well known. Giant covalent structures lattices explaining properties of diamond graphite silica what is the bonding and structure of carbon allotropes Buckminsterfullerenes fullerenes silicon dioxide gcse chemistry notes igcse A level GCE AS A2 Level.

CHEMICAL BONDING Part 4 Covalent Bonding – giant covalent structures and polymers Doc Brown's Science–Chemistry Chemical Bonding GCSE/IGCSE/O/AS/A2 Level Revision Notes DIAGRAMS of GIANT COVALENT STRUCTURES and their PROPERTIES EXPLAINED – This section describes how covalent bonds can lead to large linear ('1D') giant molecular covalent structures e.g. thermoplastic polymer macromolecules, two dimensional ('2D') structures like graphite layers and three dimensional ('3D') giant covalent structured molecules like diamond, silica and thermosetting plastics.

The physical properties of these structures are described and explained using models of their molecular structure. These notes on giant covalent structures are designed to meet the highest standards of knowledge and understanding required for students/pupils doing GCSE chemistry, IGCSE chemistry, O Level chemistry, KS4 science courses and a basic primer for AS/A Level chemistry courses. Part 1 Introduction – why do atoms bond together? Giant Ionic Lattices. Atomic Interactions - Atomic Interactions, Interaction Potential, Van der Waals Force.

Sodium Hydroxide + Hydrochloric Acid. Socrative: Chemical Bonding. Socrative: Additional Chemistry. Stern-Gerlach Experiment - Quantum Mechanics, Spin, Quantum Measurement. Periodic Table of Rock. The Periodic Table of Videos - University of Nottingham. Chemistry Teaching Resources. Thermal Decomposition. Structure and Bonding: GCSE Chemistry. GCSE Chemistry - Alkali Metals - Periodic Table - The Elements Blind Date Show - 1 of 2. Structure and Bonding: GCSE Chemistry. Hwb. Valence Bond Theory Part 4 | Classteacher Learning Systems. MC Squared by Mr Collins. Real-world Science. Writing Chemical Formulae by Rebecca Leitch on Prezi. Sixty Symbols - Physics and Astronomy videos. Models of the Hydrogen Atom - Quantum Mechanics, Hydrogen Atom, DeBroglie Wavelength. Topics Quantum Mechanics Hydrogen Atom Bohr Model DeBroglie Wavelength Schrodinger Model Description How did scientists figure out the structure of atoms without looking at them?

Try out different models by shooting light at the atom. Check how the prediction of the model matches the experimental results. Sample Learning Goals Visualize different models of the hydrogen atom.Explain what experimental predictions each model makes.Explain why people believed in each model and why each historical model was inadequate.Explain the relationship between the physical picture of the orbits and the energy level diagram of an electron.Engage in model building.

Version 1.11. Syngenta Periodic Table of Elements. Syngenta Periodic Table of Elements. Van Der Waals. Valence Bond Theory Part 4 | Classteacher Learning Systems. Neon Lights & Other Discharge Lamps - Light, Radiation, Gas. Hwb. GCSE Chemistry - Alkali Metals - Periodic Table - The Elements Blind Date Show - 2 of 2. Atoms, Elements and Compounds: GCSE Chemistry. Interactive Science Software - Atom Builder. Atom Builder allows students to investigate the properties of elements from the periodic table. Students can use this software to lookup the atomic structure of elements and change the number of protons, neutrons and electrons to produce different atoms. This is a free and complete version of LJ Create's popular Atom Builder app. You can use this software for any educational purposes. This version of the software does however have to be loaded using this web page. The app contains a periodic table reference so students can see where a particular element fits into the periodic table classifications.

Atoms, Molecules and Compounds. Chemistry. If you have an interest in anything in the world, then you have an interest in chemistry because everything you hear, see, taste, smell and touch involves chemistry and chemicals. Our ability to understand the chemical make-up of things and chemical reactions has led to everything from modern food and drugs to plastics and computers. The Center for Sustainable Polymers focuses on economical, bio-based sources for plastics NSF's Center for Selective C-H Functionalization hopes to trim the cost and environmental impact of...

Researchers have succeeded in creating the largest phytoplankton bloom in a wave flume in history as part of a... From ocean microbes to clouds and climate--it all comes down to microscopic particles at the Center for Aerosol Impacts... Center for Sustainable Materials Chemistry focuses on making computer chip manufacturing cleaner, faster and cheaper Center for Chemical Evolution tracking ancestors of RNA and DNA Paula Hammond is in pursuit of the invisible.

The Periodic Table of Videos - University of Nottingham.