In water conservation, chemists spread a thin film of a certain inert material over the surface of water to cut down on the rate of evaporation of water in reservoirs, this technique was pioneered by benjamin franklin three centuries ago. franklin found that 0.10 ml of oil could spread over the surface of water of about 40 m2in area. assuming that the oil forms a monolayer, that is, a layer that is only one molecule thick, estimate the length of each oil molecule in nanometers.

extremely tiny clusters of atoms or molecules are often called nano-particles due to the small scale of their dimensions. the specific gravity of gold is 19.3 and the mass of one gold atom is 197 amu (where 1 amu = 1.66 x 10-24g). calculate the number of gold atomsin a sphere-shaped nano-particle of gold that is 2.00 nanometers in diameter. [hint: recall that the volume of a sphere is (4/3)πr3where r is the sphere's radius and π= 3.1416.]

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11. phosphorus-32 is radioactive and has a half life of 14 days. how much of a 124 mg sample of phosphorus-32 is present after 56 days? a) 7.75 mg b) 15.5 mg c) 31.0 mg d) 62.0 mg

Many reactions take place in aqueous solution. when potential reactants are mixed, a reaction will occur if there is some driving force that favors the formation of products. it is often convenient to categorize reactions in terms of these driving forces: precipitate formation, in which an insoluble solid is formed, weak electrolyte formation, as in a neutralization reaction involving water, or transfer of electrons, as in a redox reaction. these reactions can be represented by full molecular equations, which contain all species in the reaction mixture, or by net ionic equations, which show only the species that actually undergo a change. the latter does not contain the spectator ions, which do not undergo a net change or do not take part in the reaction. part a when the following two solutions are mixed: k2co3(aq)+fe(no3)3(aq) the mixture contains the ions listed below. sort these species into spectator ions and ions that react. drag the appropriate items to their respective bins. view available hint(s) spectator ions ions that react part b what is the correct net ionic equation, including all coefficients, charges, and phases, for the following set of reactants? assume that the contribution of protons from h2so4 is near 100 %.ba(oh)2(aq)+h2so4(aq)→ express your answer as a chemical equation. view available hint(s) nothing provide feedback

What happened to the amount of carbon dioxide in the atmosphere from 2010–2017?