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# General Chemistry

### 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.

### Understanding radioactive decay, half-life and nuclear chemistry.

If you start with 64 g of a material with a half-life of 10 years, how much will be left at the end of 40 years?

### Quantum numbers

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

### Understanding relationships between energy, frequency, and wavelength

Calculate the amount of energy (in J) of a photon of light that has a frequency of 4.6x10E14 /s.

### Relationships Between Wavelength, Energy, and Frequency

Calculate the amount of energy associated with a photon of light with a frequency of 6.23 x 10E14 /s.

### Relationships between wavelength, frequency, and energy of light

Calculate the frequency, in units of "per second", of light with a wavelength of (a) 540 nm, and (b) 650 nm.

### Relationships between wavelength, frequency, and energy of light.

A certain colour of light has a wavelength of 550 nm. What is the energy possessed by a photon of such light? (a) 2.42 x 10E-19 (b) 5.45 x 10E14 J (c) 3.61 x 10E-14 J (d) 3.61 x 10E-19 J (e) 5.37 x 10E-19 J

### How to separate a mixture of oil, sand and saltwater.

How would you describe how to separate a mixture of oil, sand, and saltwater?

### Understanding the differences of alcohol contents in drinks.

Whiskey can have an alcohol content in the 50 to 60% range whereas the upper limit for alcohol content in beers and wines is only about 10%. Why is this?

### Determining which solutions will form a precipitate when mixed together.

What precipitate forms when solutions of the following are mixed: K+, Ca2+, NH4 1+, and Cl-, NO3 1-, CO3 2-?

### Understanding a scientific method.

Explain what is meant by a Scientific Method.

### Reasons for iron discolouration

A shipment of iron-fortified powdered baby formula has been rejected by the buyers in China because the power is off-color. The color of the powder should be cream-colored, but this shipment is reddish-brown to gray. Investigation by the manufacturer shows that the manufacturing process is simply "bucket chemistry". This mean

### Principal and Orbital QN

Find the following: <r> for the 2p0 <r2> for the 2p1

### Wave functions Integral Equations

Explain why each of the following integrals must be 0 when the functions are hydrogen-like wavefunctions: <2p1|Lz|3p-1> and <2p0|Lz|2p0> Show that taking the lithium spin orbitals in a Slater determinant as 1sa, 1sb, and 1s(c1a+c2b) where c1 and c2 are constants gives a wavefunction that equals zero. Tthe a and b are alp

### Isotopes and Radioactive Decay

The isotope C14 has a half-life of 5700 years. What fraction of the C14 atoms will decay (a) each year, and (b) each minute?

### Question about Calculating the ppm of Ozone in the Air

If the volume fraction of ozone in the air of a city is 5x10-7, what is the ppm of ozone in the air?

### Solve: Volume and Torr Pressure

If a gas occupies 625 mL at 0 Celsius and 760 torr pressure, what will its volume be at 373 degree C and 1520 torr pressure?

### Determining the Atmospheric Pressure of Partial Pressures

What is the atmospheric pressure if the partial pressures of nitrogen, oxygen, and argon are 77.75 kPa, 19.94 kPa, and 1.99 kPa, respectively?

### Convert Celcius to Fahrenheit

Convert 37 Celsius in to Fahrenheit

### Converting angstroms to picometers.

An angstrom is a non SI unit of measurement equal to 10^-10m. How many angstroms are equivalent to 259 picometers?

### Learning how to balance chemical equations.

What is the coefficient for water (H2O) when the following equation is balanced using the lowest whole numbered coefficients? Al(s)+ ____H20(l) --> Al(OH)3(s) + H2(g)

### Significant Digits and Unit Conversion

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.

### Writing and Balancing Chemical Equations

I need the following chemical equations written and balanced: Potassium metal is heated with powdered phosphorus to produce potassium phosphide. Cobalt (III) hydrogen carbonate decomposes by heating to give solid cobalt (III) carbonate, water, and carbon dioxide gas. Aqueous solutions of tin (II) chloride and sodium sul