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General Chemistry

Word problem: Convert uL to mL

A nurse plans to five flu injections of 50 uL (microliters) each from a bottle containing 2.0 mL of vaccine. How many doses are in the bottle? Please show steps to get answer.

Barium hydroxide

Write a balanced chemical equation, for the reaction that occurs, when Solid barium hydroxide, dissolves in water. Thank you

Calculating Vapor Pressure

The vapor pressure of a solution containing 53.6 g glycerin (C3H8O3) in 133.7 g ethanol (C2H5OH) is 113 torr at 40 degrees Celsius. Calculate the vapor pressure of pure ethanol at 40 degrees Celsius assuming that glycerin is a nonvolatile, nonelectrolyte solute in ethanol.

Half life

1) Radioisotopes such as aluminum -26, which is believed to have been present in the solar system when earth was formed but can no longer be detected, are known as extinct radionuclides. The half-life for the decay of aluminum -26 is 7.20 x 10 ^5 years. How many years did it take for 99.99% of the aluminum -26 to decay? If

Naming Complex Explanations

Cis-Co(en)2(NO2)2]+ trans-[Pt(NH3)3Cl3] I know that trans means opposite, cis and en I am not sure what that means but for some reason I am unable to identify the above complexes.

Element Compounds

What are element compounds and what are their properties? - Definition of element compounds - Properties of element compounds - Examples of element compounds - What element compounds are used for

Product Solubility

The solubility product of Ca(OH)2,is 7.9x10^-3 at 25C. Will a precipitate form when 100ml of 0.10 mol/L of CaCl2 solution and 50.0 ml of 0.070 mol/L of NaOH solution are combined?

De Broglie Waves

What is the de Broglie wavelength of a 145 g baseball traveling at 30.0 m/s (67.1mph)? Is the wavelength much larger or smaller than the diameter of an atom (on the order of 100 pm)?

Electromagnetic Waves: Radio Message from Mars

At its closest approach, Mars is 56 million km from Earth. How long would it take to send a radio message from a space probe of Mars to earth when the planets are at this closest distance?

Molar solubility

Calculate molar solubility of CuI in 1.0 M NaI. Assume the highest complex formed is CuI2 - .

Precipitation

Solid Na2SO4 is added to a solution that contains 0.150 M Ba 2+ and 0.0800 M Ca2+. Which sulfate precipitates first, BaSO4 or CaSO4? What calculations would porve this? What should be the concentration of sulfate ion for the best separation?

Wavelength from a graph

For the hydrogen spectrum, how do you find the wavelength (experimental value in nm) from a graph? I don't understand what exactly you are plotting and how to get the wavelength from the graph. For example, if your scale readings are: Violet-4.5, Blue-5.0, Yellow-6.0, Red-6.6 The same question applies to the spectra of cat

Resonance Forms of BF3

The question goes like this. Boron often forms compounds that do not comply with the octet rule that are termed electron deficient. BF3, whose structure is shown below on the left, is an example of an electron deficient compound. Note that the central boron atom is only surrounded by 6 valence electrons. The resonance struct

Chemistry Question Set

Please see the attached file for full problem description. 10a. Determine the number of CH2CH2 monomeric units, n, in one molecule of polyethylene with a molar mass of 40,000 g. 10b. What is the total number of carbon atoms in this polyethylene? 8. Equations 9.1 and 9.2 (listed below) show the polymerization of two ethy

Concentration and Dilution

Calculate the concentration of all the following. A solution of FeCl3 was prepared by dissolving 13.86 gm of FeCl3 in 2.5L of water. The following solutions were then prepared by dilution: Solution A: 75.0 mL of the above solution was diluted to 100.0mL Solution B: 100.0 mL of solution A was diluted to 2500 mL Solution C:

Determining the equation of a reaction

If 7.85 x 10 to the 24th power Sc atoms react with excess CaO, how many grams of each product will form? You will need to determine the equation of the reaction. Please show steps to solve the problem. Thank you.

Discussion of interactive/repulsive forces

A nonelectrolyte solution adsorbs on an electrically neutral solid through a liquid. Two surfaces of this type are brought close to one another in the liquid such that they interact. Will they attract or repel one another? Which equations bear this out? How does the separation distance between the two solids come into play h

Identifying chemicals by observing physical/chemical behavior

Questions 9 - 11: a) COsub3^2- b) MnOsub4^- c) NHsub4^+ d) Ba^2+ e) Al^3+ Assume that you have several unknowns each consisting of an aqueous solution of a salt that contains one of the ions listed above, which ion must be present if the following observations are made of that unknown? 9) the solution is colore

Absorption Spectroscopy Experiment

I need help describing an experiment where one could measure the value of the extinction coefficient of a solution with a concentration (c mol/L) of chlorophyll in water for a given wavelength. **This does not need to be a lengthy answer, nor does it need to describe all the materials needed---I really just need something conce

One significant figure and one conversion problem

1) How many significant figures are there in the answer to the following problem? (8.881*.02100) + .590? 2) A parsec is 206,265 times the distance from earth to the sun. If the distance is 8.000 million miles, express the distance of a parsec in miles in scientific notation.