1a )When 50.0 mL of 0.500 M HCl at 25.0°C is added to 50.0 mL of 0.500 M NaOH at 25.0°C in a coffee cup calorimeter, the temperature of the mixture rises to 28.2°C. What is the enthalpy of reaction per mole of acid? Assume the mixture has a specific heat capacity of 4.18 J/(g ? K) and that the densities of the reactant solutions are both 1.00 g/mL.

1b) Consider the following reaction: 2 PbS (s) + 3 O2 (g) ? 2 PbO (s) + 2 SO2 (g) ?H = -827.4 kJ How many grams of PbS have reacted if 975 kJ of heat is produced? 1c) Consider the following reaction carried out under constant pressure 3MgO(s) + 2NH3(g) ? 3H2O(l) + Mg3N2(aq) ? Hrxn = 5.78×102 kJ Calculate the heat associated with the complete reaction of 46.0 g of MgO with 17.1 g of NH3.

1.  Discuss the process of water boiling from the molecular point of view. Your explanation should include the effect of atmospheric pressure and the effect of adding a non-volatile solute to the water.

2. Compare and contrast Boyle’s Law and Charles’ Law. Make sure to define and explain both laws prior to discussing their similarities and differences.

Chemical Pairs: sodium chloride versus sodium chlorite barium sulfate versus barium sulfide sodium nitrate versus sodium nitrite sodium hypochlorite versus sodium perchlorate Questions: What are some of the common uses for each of the chemicals in your pair? What are some of the safety concerns for each of these chemicals? (It might help to look up the SDS for each chemical) How are the properties and safety concerns of these two chemicals different? Are they similar? What do you think could happen if you used the opposite chemical in one of the common uses you researched above? What are some of the consequences that could occur? Be sure to include an example for both chemicals you looked up.Chemical Pairs: sodium chloride versus sodium chlorite barium sulfate versus barium sulfide sodium nitrate versus sodium nitrite sodium hypochlorite versus sodium perchlorate Questions: What are some of the common uses for each of the chemicals in your pair? What are some of the safety concerns for each of these chemicals? (It might help to look up the SDS for each chemical) How are the properties and safety concerns of these two chemicals different? Are they similar? What do you think could happen if you used the opposite chemical in one of the common uses you researched above? What are some of the consequences that could occur? Be sure to include an example for both chemicals you looked up.

A 2.20 g sample of the Ethane C2H6 gas was mixed with excess oxygen gas and a combustion reaction occurred to obtain water in liquid aggregate and carbon dioxide state. The combustion reaction occurred at a constant calorimeter under standard conditions.
After the reaction was completed, the temperature in the calorimeter rose by 1.3K. The heat capacity of the calorimeter is 88.8 kJ / K.

1. Write a balanced response to the burning process that took place.
2. Consider the change in standard enthalpy, ∆H for a 1 molar reaction of ethane. Show calculations.
3. Explain how you would calculate ∆H_f [C₂H₆(g)] given you values ​​of:
∆H_f [CO₂(g)] and ∆H_f [H₂O(l)]
Numerical calculations are not required.
4. Determine what the missing data is to calculate the change in the fire enthalpy,
∆H_c of ethane at 100 C?
5. Is a difference between ∆H^o and ∆U^o expected for the reaction formulated in section a? Explain

A-- 1.25 cubic inch (in3) sample of glycerol has a mass of 25.2 grams. What is the mass of a 57-mL sample of glycerol?

b---The pressure of the earth's atmosphere at sea level is 14.7 lb/in2 (pounds per square inch). What is the pressure when expressed in g/m2 (grams per square meter)? (2.54 cm = 1 in., 2.205 lb = 1 kg)

c---Solid calcium oxide is reacted with solid carbon to form calcium carbide (CaC₂) and carbon dioxide.

Write a balanced chemical equation that describes this reaction. (3 points)

If the reaction is carried out using 100.00 grams of calcium oxide and 100.00 g of carbon, how many moles of each reactant are used? (2 points)

d---Ammonium sulfate is primarily used as a fertilizer for alkaline solids. In the soil the ammonium ion is released and forms a small amount of acid, lowering the pH balance of the soil, while contributing essential nitrogen for plant growth.

What is the chemical formula of ammonium sulfate? (1 point)

What is the mass percentage of nitrogen in ammonium sulfate? (2 points)

How many moles of ions are released when 13.2 g of ammonium sulfate is dissolved in water? (2 points)

Many radioactive isotopes are used in medicine for imaging and treatment purposes. The specific isotopes used depends on the particular organ or body system being studied (for example, Xe-133 is used to image lung function and blood flow.) For thyroid imaging, isotopes of iodine are used, commonly I-123 and I-131, which have half-lives of 13.2 hours and 8.0 days, respectively.

Why is iodine used for thyroid imaging (as opposed to any other element)?

I-129 is an extremely rare isotope of iodine with a half-life of 15.7 million years. Assuming it was much more abundant in nature, would I-129 be a good substitute for I-123 or I-131 in thyroid imaging? Why or why not?

Although both I-123 and I-131 can be used in imaging of the thyroid, only I-131 is used in treating thyroid cancer. What difference in radioactivity between I-123 and I-131 accounts for this preference?

Sometimes non-radioactive isotopes of iodine can be preferred depending on the intended medical use. For example, many people preparing for a nuclear disaster stockpile KI tablets (non-radioactive). Why would someone consume KI during a radioactive disaster? Would you consider purchasing KI tablets as a precaution? Why or why not?

2.15 mol of an ideal gas with CV,m=3R/2 undergoes the transformations described in the following list from an initial state described by T=350.K and P=5.00bar.

1) The gas undergoes a reversible adiabatic expansion until the final pressure is one-fourth its initial value.

2) The gas undergoes an adiabatic expansion against a constant external pressure of 1.25 bar until the final pressure is one-fourth its initial value.

3)The gas undergoes an expansion against a constant external pressure of zero bar until the final pressure is equal to one-fourth of its initial value.

a) Calculate q for each process. (q1,q2,q3)

b) Calculate w for each process. (w1,w2,w3)

c) Calculate ΔU for each process. (ΔU1, ΔU2, ΔU3)

d) Calculate ΔH for each process. (ΔH1, ΔH2, ΔH3)

e) Calculate ΔS for each process. (ΔS1, ΔS2, ΔS3)

what other techniques are similar to protein crystallization?

1)Let’s say that you recovered 80% trimyristin (after recrystallization, so the final product) from the 2 g of nutmeg you initially started with.

a- If you completed the hydrolysis reaction (see lab) to make myristic acid and glycerol, what would be your theoretical yield of myristic acid?

b- If you recovered 1.72 g of myristic acid, what would be your percent recovery of myristic acid?

c- What might account for sources of error in your recovery?(Give 3 plausible reasons)

PLEASE SHOW ME YOUR STEPS!!

Consider the following unbalanced redox equations: a. I

Describe what is meant by an electrical double layer (EDL) that occurs at the interface between an electrode and the solution

Discuss Dalton’s theory. What are all of the postulates? With recent discoveries about the nature of an atom, does it still apply today?

Describe electronegativity and relate it to the bonds water makes.