Explain resonance stabilization from the MO perspective
In: Chemistry
first, discussion about Essential Elements
Some elements are essential to our health, like oxygen that makes up carbohydrates, fats, proteins, and DNA. Mention another two elements (essential or non-essential) and discuss their function in our body and why they are important to the well-being of human body. Do not repeat other students answers.
Second, respond for this guy he said ( There are many important elements that make up our body. One of those elements is calcium. Calcium is important because it keeps our bones and teeth strong and healthy. This gives our body skeletal structure and protects our organs. Phosphorus is another important element in the body. It works in conjunction with calcium to keep bones and teeth strong and healthy. It is also needed in the body to make protein for growth, repair, and maintenance of cells and tissues. It is very interesting how the elements are at work in our body.)
In: Chemistry
Calculate [Ag1+] in solution at equilibrium when 2.39 x 10-2 M AgNO3 is added to 1.00 L of a 1.65 M NH3 solution, assuming no volume change? (Kf for Ag(NH3)21+ is 1.1 x 107)
a) 3.8 x 10-2
b) 2.39 x 10-2
c) 4.9 x 10-11
d) 8.5 x 10-10
e) 4.1 x 10-3
In: Chemistry
Clearly and concisely explain how ionic (ion exchange) tempering of glass increases its strength (note that this is really two questions-1) what is ionic tempering? and 2) how does it affect glass properties?)
Please explain in a good words!!! Thanks
In: Chemistry
In: Chemistry
You wish to prepare 50.00 mL of 0.0600 M NH3 from concentrated ammonia (15.28 M) by serial dilution using a 50 mL volumetric flasks, a 1.00 mL volumetric pipet, and a 10.00 mL graduated pipet.
For the first dilution in the series, 1 mL of concentrated ammonia is added to a 50.00 volumetric flask and then filled to the line. The solution is mixed thoroughly, poured into a beaker, and then used to make the second solution in the series. What volume of the first solution should be used to make the second solution, 50.00 mL of 0.0600 M NH3 solution
In: Chemistry
1.) Explain the following observations in terms of shifting equilibria by Le Chatelier's Principle. Write the equation for the equilibrium involved in each case.
a.) barium chromate, BaCrO4, is insoluble in basic solution but dissolves readily in acidic solution.
b.) The addition of NaOH to the iron (III)- thiocyanate equilibrium causes the red color to disappear and a rust colored precipitate to form.
c.) The solubility of lead chloride, PbCl2, in 0.10 M HCl is much lower than in pure water.
d.) Limestone, CaCO3, is an insoluble salt but will dissolve in acid.
e.) For part C, how does the rate of the reaction vary as the temperature is increased? Explain.
In: Chemistry
Balance the following skeleton reactions and identify
the oxidizing and reducing agents:
MnO4-(aq) + CN-(aq) --> MnO2(s) + CNO-(aq) [basic]
In: Chemistry
Can you balance these redox equations? I am having trouble figuring out the process of adding extra products to make them work.
ClO3- + Cl- -----> Cl2 + ClO2-
Cr2O72- + C2O42- -----> Cr3+ + CO2
In: Chemistry
Tungsten trioxide (WO3) has a rich yellow color and is often used as a pigment in ceramics and paints. In order to test a ceramic vase for its WO3 content, a 10.05 g sample of the vase was ground and reduced with Pb(Hg) to convert any WO3 to W3 . The resulting W3 was transferred to 500.0 mL of 1.00 M HCl. A 100.00 mL aliquot of the HCl solution required 13.50 mL of 0.08202 M potassium permanganate (KMnO4) to reach the purple endpoint. A blank required 0.06 mL. Balance the reaction below and determine the percent WO3 in the ceramic sample.
In: Chemistry
3. Calculate the density of NO at STP and at 20.0 C and 720 torr.
4. The volume of a mass of gas is 300 ml at 25 C and 685 torr. What volume will the gas occupy at STP?
5. Calculate the weight of hydrogen in 750 ml of hydrogen gas collected over water at 25.0 C and 0.895 atm. (vp of water at 25 C = 23.0 mm)
In: Chemistry
1. Vinegar consists of acetic acid, CH3COOH, and water. Write out the equilibrium expression for acetic acid reacting with water.
2. Citric acid, H3C6H5O7, contributes to the acidity of many foods. Write out the equilibrium expression for citric acid reacting with water to lose one acidic proton.
In: Chemistry
A scientist would like to use thermal diffusion to dope the silicon wafer. He decides to deposit 10 nm Boron on the surface and heat up the wafer to allow Boron to diffuse into the wafer. What technique do you recommend him to use to deposit high purity Boron on the surface? Explain what are the machines he could use and what kind of precursors he needs to use.
In: Chemistry
The compound known as butylated hydroxytoluene, abbreviated as BHT, contains carbon, hydrogen, and oxygen. A 1.126 g sample of BHT was combusted in an oxygen rich environment to produce 3.373 g of CO2(g) and 1.105 g of H2O(g). Insert subscripts below to appropriately display the empirical formula of BHT.
In: Chemistry
In: Chemistry