Low density polyethylene (LDPE) – involves an older gas phase process (still used) with conditions: high pressure (1000-3000 times atmospheric), high temperature (300°C) and an initiator (an organic peroxide e.g. dibutyl peroxide, or oxygen). The resultant product has significant chain branching due to alkyl groups replacing hydrogen atoms on some carbon atoms. Consequently, the alkane chains cannot pack together in an orderly fashion, resulting in low densities and weak dispersion forces; therefore LDPE is soft, flexible and has a low melting point. The initiator isn’t strictly a catalyst as it is involved in the actual formation (one initiator molecule per ½ polymer molecule).
Why or Why not? There is not any free rotation because the amino Nitrogen has a lone pair that can form a partial double bond character with the carbonyl group. This characteristic resists free rotation.. 4) Is there free rotation around the Cα-COO bond (aka the ψ bond)? Why or Why not? There is free rotation around this group because resonance is limited to resist the free rotation.
Seventy five percent of the table is made up of metals, and a couple of the columns on the right of the table have gases. There are only two elements that are liquids- mercury and bromine. Column 1 contains the alkali metals, which suddenly combust when exposed to air or water. Columns 3-12 are the transition metals, which contain heavier atoms, which are more flexible in how they organize their electrons. Column 17 is made up of the more reactive gases- the halogens.
CHEM 2124 Unit 2 Worksheet 2 1) Why does benzene undergo a substitution reaction with Br2 while cyclohexene undergoes an addition reaction? Addition of bromine to benzene is highly unfavorable because it would result in a non-aromatic product. 2) Which is more stable, cyclobutadiene or 1,3-butadiene? Explain 1,3-butadiene is more stable. Cyclobutadiene is antiaromatic and antiaromatic systems are less stable than their open chain counterparts.
BIOL-110 Elements of Biology Assignment 1 Student Name: Part A: Multiple Choice Questions and Fill in the Blanks 1) A covalent chemical bond is one in which * c) Outer-shell electrons of two atoms are shared 2) Which of the following is not a weak molecular interaction? * a) A covalent bond 3) Polysaccharides, lipids, and proteins are similar in that they * b) Are synthesized from monomers by dehydration reactions. 4) Which of the following is a compartment that often takes up much of the volume of a plant cell? * b) Vacuole 5) The presence of cholesterol in the plasma membranes of some animals * a) Enables the membrane to stay fluid more easily when cell temperature drops 6) Which of the following types of molecules are the major structural
Number – 19g average mass 1.7g 4) If a 4th isotope of beanium, D (green), were added to the pool, how would the average atomic mass change? Mixture of an element and a compound, changing the subscript changes of the compound. 5) Compare your average atomic mass to that group next to you. Why is the number slightly different? Would the difference be larger or smaller sizes were used?
7. Archaega does not have cell wall but they do compose of peptidoglycan molecules with the exception of methanobacteria who have pseudo peptidoglycan in their cell wall. 8. There are three main types of archaea: the crenarchaeota which are characterized by their ability to tolerate extremes in temperature and acidity. The euryarchaeota which include methane-producers and salt-lovers; and the korarchaeota catch-all group for archaeans about which very little is known.
Strong electrolytes produce large numbers of ions, which results in high conductivity values. Weak electrolytes result in low conductivity, and non-electrolytes should result in no conductivity. In this experiment, you will observe several factors that determine whether or not a solution conducts, and if so, the relative magnitude of the conductivity. Thus, this simple experiment allows you to learn a great deal about different compounds and their resulting solutions. In each part of the experiment, you will be observing a different property of electrolytes.
Lab Report: Macromolecules Macromolecules are large organic molecules that are typically found as polymer chains which are composed of many monomer subunits. Nucleic acids, proteins, carbohydrates and lipids are all examples of macromolecules commonly found in cells. These are found in all living things. In the experiments we tested organic samples for the presence of nucleic acids, proteins carbohydrates, and lipids. We were given unknown 4, and based on our unknown given our sense observation, besides tastes of course; we concluded that it was high in sugar.
A molecular orbital is merely a Schrödinger orbital which includes several, but often only two nuclei. If this orbital is of type in which the electron(s) in the orbital have a higher probability of being between nuclei than elsewhere, the orbital will be a bonding orbital, and will tend to hold the nuclei together. If the electrons tend to be present in a molecular orbital in which they spend more time elsewhere than between the nuclei, the orbital will function as an anti-bonding orbital and will actually weaken the bond. Electrons in non-bonding orbitals tend to be in deep orbitals (nearly atomic orbitals) associated almost entirely with one nucleus or the other, and thus they spend equal time between nuclei or not. These electrons neither contribute nor detract from bond strength.