foods from changing the pH of the digestive system. 4. Define a molecule and a compound. Compare and contrast ionic and covalent bonds. Molecule is the smallest unit of an element or compound, made up of two or more atoms held together by strong chemical bond. Compound is a molecule made up of atoms of two or more elements bonded together. The difference between ionic bonds and covalent bonds are their shape, their state of matter at room temperature, and their melting point. Ionic bonds have…
which an unstable atomic nucleus loses energy by emitting radiation. Each radioisotope decays at its own fixed rate and this is measured in half lives. As discussed in Lesson 6, this is the time it takes for half of a parent element (e.g. uranium) to decay into a daughter element (e.g. lead) [1]. A common method of radioactive dating is ‘uranium-lead dating’. Which looks at the amounts of Uranium and determine how much has decayed…
associated with human diseases. Our current knowledge of chemical induced adverse health effects is mainly limited to the toxicity of the individual chemicals. For the majority of chemicals, its individual toxicity is well documented, examples arsenic and skin, lung and bladder cancers; dioxin and chloracne; lead and neurotoxicity; benzo[a]pyrene and lung cancer. The scientific community increasingly recognizes the adverse effects associated with chemical mixtures are a serious concern. The task…
periodic table, which is for the most part appeared at the bottom of the periodic table. This element has 67 protons in its nucleus, which implies it is the 67th component on the periodic table. Holmium is pliable, which infers it can be bowed and folded. It is the foremost magnetic component of the periodic table. The name comes from the element lanthanum. The lanthanides are also known as rare earth elements. Although lanthanides are not especially rare, they are very difficult to separate…
you're suddenly handed a mysterious vial that inside holds a white mixture. You’re told that you have to figure out what is in it using physical and chemical properties to help you! What is a physical and chemical property you may be asking. A physical property is something you can touch, feel, smell, hear, and see so you’re using your human senses. A chemical property is when the physical property has been changed and now you see gas being produced, temperature changes, and smell different…
: The chemical formula of a compound will be determined using the mass of each individual element that is present in a weighed sample of that compound. The chemical formula shows the proportions of elements in a specific compound. This proportion is uniform to all samples of the same compound. Using the mass of each element, the moles of the element in the compound can be found and then compared to that of the other elements. This will create our atom ratio which will lead to our mole ratio. The…
overall significance to biological systems, reactions were done in order to test the types of reaction types associated with copper. In addition, vacuum filtration methods and detailed observations were taken on how copper reacts with different chemicals as it is constantly heated and mixed. Towards the end of the experiment the remaining amount of copper is eventually recovered and analyzed. Materials and Methods: The most important part of the experiment as a whole was of course completing…
Mendeleev lived and worked before there was a consensus on the constitution of an atom. Were they solid and uniform throughout with only mass differentiating between elements, or were they particulate and composed of certain “sub-atoms”? Mendeleev staunchly adhered to the former theory and explained certain phenomenon characteristic of electrons and protons (valence properties, radioactivity) as a result of this ether…
Chemistry is the study of atoms. Chemical scientists study what atoms are made of and how they connect. Atoms are the building blocks of matter. Atoms are made up of protons, neutrons and electrons. It was John Dalton who put forward his ideas and theories about atoms at the beginning of the 19th century: Dalton proposed that atoms were like tiny, hard balls (Absorb Learning, 2008). Then at the end of the 19th century JJ Thompson discovered the electron through an experiment. When JJ Thompson…
discovered that some of the neutrons would be knocked out. James then took the opportunity to measure their energy. The discovery of the neutron made it possible for scientist to create their own experiment in were they would bombard elements. Eventually the elements would undergo fission a type of nuclear reaction. The neutron has also become a tool of pure research and has been used to understand the structure of…