1. What is the molarity of a solution that contains 18.7 g of KCl (MW=74.5) in 500 mL of water?
   
2. 25 g of NaOH (MW = 40) is added to 0.5 L of water. What is the molarity of this solution if an additional 0.25 L of water is added to this solution?
   
3. How many grams of H₂SO₄ (MW = 98) are in 750 mL of 3 N H₂SO₄?
   
4. What is the normality of a solution that contains 280 g of NaOH (MW=40) in 2000 mL of solution?
   
5. A serum potassium is 19.5 mg/100 mL. This value is equal to how many mEq/L (MW = 39)?

You are given a series of 5 tubes, each of which contains 5 mL of saline. To the first tube is added 1 mL of serum, and a serial dilution using 1 mL is carried out in the remaining tubes.

6. What is the dilution in the first tube?
7. What is the final dilution in the third tube
8. The third tube was run, and the triglyceride concentration was 3 mg/dL. Give the triglyceride concentration in the 1^st tube:
9. What is the concentration of the original specimen?
10. What result do you report out?

Consider an ionic compound, MX2MX2 , composed of generic metal MM and generic, gaseous halogen XX .

• The enthalpy of formation of MX2MX2 is ΔH∘f= −817ΔHf∘

• The enthalpy of sublimation of MM is ΔHsub= 115ΔHsub

• The first and second ionization energies of MM are IE1= 717IE1 and IE2= 1395

• The electron affinity of XX is ΔHEA= −323 kJ/mol. (Refer to the hint).

• The bond energy of X2X2 is BE= 165 kJ/mol.

Determine the lattice energy of MX2MX2 .

ΔHlattice=______kJ/mol

I start with 3 mL of [Ru(bpy)3](PF6)2 solution. Every time Add 100 uL volume of DPA solution with 0.05M. Do it five times, the total amount of DPA is 500ul

500ul

I am so confused about how to calculate the concentration of DPA in each adding

Express your answer in complete form in the order of orbital filling as a string without blank space between orbitals. For example, 1s22s2 should be entered as 1s^22s^2.

1. Ca2+

2. K+

3. S2−

4. Br-

Rank the following 0.10 M solutions in order of increasing pH. (Use the appropriate <, =, or > symbol to separate substances in the list.)

(a)    HBr, LiBr, HF, LiF

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(b)    HI, RbI, NH₃, NH₄I

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(c)    C₅H₅NHNO₃, C₅H₅N, HNO₃, LiNO₃, LiOBr, HOBr, LiOH

for a diatomic perfect gas , derive the equation for entropy S , enthalpy H , Gibbs energy G . and Helmholtz energy A

A mixture of 136.4 g136.4 g of Cl2Cl2 and 29.8 g29.8 g of PP reacts completely to form PCl3PCl3 and PCl5.PCl5. Find the mass of PCl5PCl5 produced.

A student states that sulfates are bad for our planet because they warm the planet. Now that you have a much greater understanding of the chemistry of various molecules, please help enlighten this student.

history of Nanotechnology

Congenital Galactosemia typically appears only in infants because with maturation, most children develop another enzyme capable of metabolizing galactose. Its incidence is about 1 per 18,000 births. If the infant does not receive treatment then there is a 75% chance of death. Thus, in the United States infants are screened for galactosemia. Galactosemia can be confused with lactose intolerance but galactosemia is a considerably more serious condition because consumption of galactose can cause permanent damage to their bodies. What dietary changes should be made?

Compound (A) forms only proprionaldehyde (B) upon ozonolysis and reduction with (CH3)2S. Treatment of (A) with aqueous chlorine affords (C) (C6H13ClO). Exposure of (C) to aqueous NaOH produces racemate (D) (C6H12O). (Think about intramolecular SN 2 reaction Williamson ether synthesis). Compound (D) is also formed by the reaction of peracid with (A). What are the structures of (A), (B), (C) and (D)? Illustrate and explain. Show mechanism of aqueous chlorine reaction and indicate the arrows and lone pairs.

The following reaction forms 15.8 g of Ag:

2 Ag2O---> 4 Ag + O2

What total volume of gas forms if it is collected over water at a temperature of 25 and a total pressure of 752mmHg?