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General Chemistry

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.

Chemistry - Gases

Chemistry - Gases Using "dimensional analysis" show that 1 L kPa = 1 J. Hints : P= F/A; 1 Pa = 1 N/m^2; energy = F x d

How long animacules in meters?

Anton Von L. a 17th century pioneer in the use of the microscope, described the microrganisms he saw as "animalcules" whose length was "25 thousandths of an inch." How long were the animalcules in meters.

Conversion Factors of Meters, Micrometers, and Kilometres

I am having a problem really understanding conversion factors between meters, centimetres, and kilometres. Where do I get the conversion factor? Can you give me a step-by-step on how to solve them? Please use conversion factors to convert 4.2 yards to meters, centimeters, micrometers and kilometers. Thank you.

Molecular weight and mole concept

Write a balanced equation for: Aluminum chloride reacts with copperII carbonate Then solve: if 45 grams of copperII carbonate is used how much Aluminum carbonate will be formed(in grams).

Molecular weight and mole concept

For the reaction of nitric acid with calcium hydroxide, predict how much water is produced (in grams) from 46grams of calcium hydroxide.

Balance a Reaction Function

Balance and find moles and grams of the remaining reactants & products for the following: Barium flouride and lead nitrate react and form 6.2g of lead fluoride

Pi and Sigma bonds

Why or why isn't it possible to have pi bonds between two atoms without there being a sigma bond?

Reaction from Sodium Bisulfite Solution

In an experiment, sodium bisulfite solution is added at the end in order to destroy the unreacted bromide. What reaction is occurring here? Is HSO3- acting as an oxidizing or reducing agent? Write a balanced equation as part of your answer.

Dalton's Law of Partial Pressure

A mixture of helium and neon gases is collected over water at 28.0 C and 745 mmHg. if the partial pressure of helium is 368 mmHg, what is the partial pressure of neon?

Finding the number of molecules of a virus

A certain strain of tobacco mosaic virus has Mm = 4 *10^7 kg/k mol. How many molecules of the virus are present in 1 cm^3 of a solution that contain0.1mg of virus per cm^3

Finding volume in a molarity problem

What volume, in milliliters, of a 2.00 M aqueous KOH solution would be needed to neutralize a) 110.0 mL of 0.0550 M aqueous H2SO4? b) 45.00 mL of 2.50 M aqueous HCl?

Avagadro number

How do you do this problem? What is the number of nitrogen atoms contained in 9.40 g of N2O3

Finding the relative humidity

A closed vessel contains moist air at 20 degree celcius, the relative humidity being 30 %. What would be the relative humidity become if the vessel were cooled to 10 degree celcius ? SVP of watyer at 20 deg celcius = 17.5 mm SVP of water at 10 deg celcius = 9.2 mm

How much energy does a hydrogen atom give up?

A Hydrogen atom, treated as a point mass, is confined to an infinite one-dimensional square well of width 1.0nm. How much energy does it have to give up to fall from the level with 5 to the lowest energy level? The answer needs to be in Joules. This problem deals with quantum part of Physical chemistry.

Quantum numbers

Which element(s) has an outermost electron that could be described by the following quantum numbers: (3,1,-1,+1/2) ?