Temperature and Observations for Heating Curve.

Questions

C. Describe the key characteristics for the three states of matter.

D. Define the melting point. What was the observed melting point of water?

E. Define boiling point. What was the observed boiling point of water?

F. What happens to heat energy when it is not increasing the temperature of the substance in the beaker? Use your heating curve to explain your answer.

G. Was temperature perfectly constant during your test while the water was melting and while it was boiling? Explain why or why not. H. The published melting point of H2O is 0°C, and the published boiling point is 100°C. Why may you have found different values?

I. Use the following information to determine if the intermolecular forces of isopropyl alcohol are greater or weaker than the intermolecular forces of water. Explain your answer. The melting point of isopropyl alcohol (rubbing alcohol, C3H8O) is about -90°C and the boiling point is about 82°C.

The Haber-Bosch process is a very important industrial process. In the Haber-Bosch process, hydrogen gas reacts with nitrogen gas to produce ammonia according to the equation

3H2(g)+N2(g)→2NH3(g)

The ammonia produced in the Haber-Bosch process has a wide range of uses, from fertilizer to pharmaceuticals. However, the production of ammonia is difficult, resulting in lower yields than those predicted from the chemical equation.

1.14 g H2 is allowed to react with 10.1 g N2, producing 1.47 gNH3.

Part A

What is the theoretical yield in grams for this reaction under the given conditions?

Express your answer to three significant figures and include the appropriate units.

Part B

What is the percent yield for this reaction under the given conditions?

3) What is Rayleigh scattering? Given an excitation wavelength of 350 nm and an aqueous solution, at what wavelengths would you expect to see the Rayleigh scattering peaks in the emission spectrum?

4. Why are anti-Stokes shifts the least common phenomenon compared to Stokes or Rayleigh scattering?

Look up the following materials and say which class of magnetic response you would expect each to be.

a. chromium   b. Magnetite c. cobalt d. oxygen e. nitrogen   f. iron oxide   g. platinum    h. Alnico   i. SmCo₅

Questions:

1. Explain two things in the procedure that may reduce the final percent yield.
2. The K₃[Fe(C₂O₄)₃]·3H₂O crystals are green. The compound absorbs light at 675 nm.
   1. What color of light does this correspond to in the visual light section of the electromagnetic spectrum?

2. Compare your answer in part a to the observation of green crystals. Is the color you see the absorbed color or transmitted color?

calculate delta g for the reaction between Cr (S) and Cu 2+ (aq)

In the extraction of trimyrisitn from nutmeg:

Why was diethyl ether used as the extraction solvent instead of using acetone directly, since you were going to recrystallize using acetone anyway

How would your results be different (if at all), if the reflux was only done for 10 minutes? Briefly explain

Why is the technique of reflux generally used in organic chemistry

An aqueous solution known as Ringer's lactate is administered intravenously to trauma victims suffering from blood loss or severe burns. The solution contains the chloride salts of sodium, potassium, and calcium and is also 3.6 mM in sodium lactate (NaC3H5O3). How many grams of sodium lactate are needed to prepare 8.5 liters of Ringer's lactate?

Experiment: Antacid tablets will be analyzed for their ability to neutralize acids. Specifically the quantity of 'simulated stomach acid' neutralized by the antacid.

Question: Why was methyl red used as an indicator in the experiment rether than phenolphthalein? (endpoint between pH 8 and 10)

Which of the following situations will produce a precipitate?

A solution containing 0.0030 M Ca2+ and 0.025 M CrO42- (Ksp for the possible CaCrO4 = 7.1 × 10-4).

A solution containing 0.095 M Tl+ (thallium(I)) and 0.0020 M Cl- (Ksp for the possible TlCl = 1.9 × 10-4).

A 500 mL solution containing 9.0 × 10-4 mol Sr2+ and 1.0 × 10-4 mol HPO42- (Ksp for the possible SrHPO4 = 1.2 × 10-7).

A solution containing 1.2 × 10-3 M Ba2+ and 1.2 × 10-2 M F- (Ksp for the possible BaF2 = 1.8 × 10-7).

The 1s--> 2p transition in a hydrogen-like ion occurs at 7.10704x10⁵ cm^-1
.
a. What is the ionization energy of this atom in Joules?
b. If this atom is ionized with light with a wavelength 4.00 nm, what is the de Broglie
wavelength of the ejected electrons?

The formation constant* of [M(CN)6]4– is 2.50 × 1017, where M is a generic metal. A 0.160-mole quantity of M(NO3)2 is added to a liter of 1.240 M NaCN solution. What is the concentration of M2 ions at equilibrium?

What is the pH of a solution that is 0.10 M KNO2 and 0.15 M HNO2? (Common ion)

at 1000degrees C the value of equilibrium constant for the reaction below is 1.62. how many moles of each compound will there be at equilibrium if 1 mole of h2, 2 moles of co2, and 3 moles of co are placed in a 10 liter tank and heated to 1000 C? H2 (g) +aCO2 (g)-----H2O(g) + CO(g)