Questions
1. For each set of atoms/ions, write them in increasing order of size (smallest to largest)...

1. For each set of atoms/ions, write them in increasing order of size (smallest to largest) a. Mg2+, Se2- , S2- , K+ , Ca2+ b. Ga, Si, Rb, N, In c. A2+, B+ , C, D- , E2- if these elements are isoelectronic (same number of electrons) d. Put the following elements, S, Ba, Bi, Cl, Te, Ar in order of increasing ionization energy, and increasing electron affinity.

2. The following questions involve the following atoms: Ge, As, K, N, O a. Draw the Lewis symbol for each atom b. Put the atoms in order of increasing electronegativity c. If any two atoms in the above list could be paired to make a bond, which two would lead to the most polar bond?

3. Calculate the lattice energy of MgCl2: MgCl2(s)Mg2+ (g) + 2Cl- (g) given the following: The sum of the 1st and 2nd ionization energy required to make Mg2+ is 2189 kJ/mol The heat of formation of Cl(g) is 121 kJ/mol The heat of formation of MgCl2 is -641.6 kJ/mol The electron affinity of Cl(g) is -349 kJ/mol The heat of formation of Mg(g) is 147.1 kJ/mol

4. Out of the following ionic compounds LiCl, Li2O, Na2S, BeF2, Al2S3, CaS a. Put them in order of increasing bond distance between the cation/anion, lowest to highest (Li-O distance in the formula unit Li2O). Use Figure 7.8 from text. b. Put them in order of increasing (lowest to highest) lattice energy

5. Draw Lewis structures (octet rule) for the following molecules: HCN, SF3 + , CH2Cl2, ClF3, BO3 3- , CH2CCl2 (the two carbon atoms are bonded to each other), CH3OH. If a double or triple bond is required, state your reasoning as to why you came to that conclusion.

6. Two Lewis structures for BF3 are given below. Determine the formal charge for each atom (write the formal charge next to the atom) in both structures and identify the correct structure. Redraw these structures on your homework.

7. Incorrect Lewis dot structures for PCl3 and CCl2O are given below. Disregarding any resonance considerations, identify the mistakes (explicitly state the mistake) in the list of instructions that led to the drawing of these incorrect structures.

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Good evening! I have synthetized benzocaine by Fischer esterification of para-aminobenzoic acid with ethanol and concentrated...

Good evening!

I have synthetized benzocaine by Fischer esterification of para-aminobenzoic acid with ethanol and concentrated H2SO4 . Product was collected by vacuum filtration and tested for melting point. Results is 79-81 while literature value is 88-90. Also Yield was 59%.

Could you please describe the way how this compound could be purified further (in detail please if it possible)

Many thanks!

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A 1.05 gram sample of butter is refluxed with ethanolic KOH and required 10.4 mL of...

A 1.05 gram sample of butter is refluxed with ethanolic KOH and required 10.4 mL of 0.1875 M HCl to reach the phenolphthalein end point. If blank determination required 27.7 mL of the same standard acid, calculate the saponification value. Calculate the saponification number. Assuming butter comprised mainly of fat, what is its molar mass?

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1 a). Write down the Slater determinant for Lithium. Expand the determinant into linear combination of...

1 a). Write down the Slater determinant for Lithium. Expand the determinant into linear combination of products.

b). Write down the Slater determinant for Beryllium. Expand the determinant into linear combination of products.

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Calculate the cell potential and the equilibrium constant for the following reaction at 298 K: Co2+(aq)...

Calculate the cell potential and the equilibrium constant for the following reaction at 298 K: Co2+(aq) + 2I-(aq) Co(s) + I2(s) Hint: Carry at least 5 significant figures during intermediate calculations to avoid round off error when taking the antilogarithm. Equilibrium constant:

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determiting the percent water in a compound. how important is to remove water from a compound...

determiting the percent water in a compound. how important is to remove water from a compound and what is the benefit of it?

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Exercise 2: Beer’s Law Curve and Unknowns Data Table 1. Concentration and Resistance. Tube Label Concentration...

Exercise 2: Beer’s Law Curve and Unknowns

Data Table 1. Concentration and Resistance.

Tube Label

Concentration of Blue Dye in Test Tube (M)

Resistance Reading on Colorimeter (Ω)

B

2.57 x 10-4 M

3.6

1

3.4

2

3.3

3

3.1

4

3.0

5

2.9

6

2.8

7

2.7

8

2.6

9

2.4

W

0 M

2.2

CD 1

2.7

CD 2

2.4

How do I fill the blanks in? I understand that I am suppose to use M1V1 but I am COMPLETELY lost.

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1. how would you appropriately label a reagent ? 2. What are the components of a...

1. how would you appropriately label a reagent ?

2. What are the components of a dipstick ? choose two and discuss their significant.

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1. The free energy available from a 1.78V Fe(III) – Ag cell under standard conditions is:...

1. The free energy available from a 1.78V Fe(III) – Ag cell under standard conditions is:

a. -515 KJ

b. +515 KJ

c. +172 KJ

d. -172 KJ

2. What is the nuclear binding energy for a mole of lithium-7 (Li-7), whose mass is 7.01600? (mass of a proton = 1.00728 AMU; neutron = 1.00866)

a. 6.34 x 1017J

b. 6.34 x 1014J

c. 3.64 x 1012J

d. 3.44 x 1015J

3.  Tc-99 is commonly used in nuclear medicine studies. It has a half-life of 6 hours. How long does it take for less than 1% of the original injected isotope to remain?

a. 24 hours

b. 30 hours

c. 36 hours

d. 42 hours

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A 5.00 M stock solution of HCl is serially diluted three times, starting with 10.00 mL...

A 5.00 M stock solution of HCl is serially diluted three times, starting with 10.00 mL and adding it to 90.00 mL of water each time. What is the final concentration of HCl in mol/L, after the third dilution?

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For the following cases, determine the ratio of the fugacity in the final state to that...

For the following cases, determine the ratio of the fugacity in the final state to that in the initial state for steam undergoing the isothermal change of state:

a) From 9000 kPa and 673.15 K to 300 kPa

b) From 7000 kPa and 700 K to 345 kPa

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In going from hydrogen to helium, what do the changes in atomic radius (37 to 32...

In going from hydrogen to helium, what do the changes in atomic radius (37 to 32 pm) and ionization energy (1311 kJ/mole to 2377 kJ/mole) suggest about the relative magnitudes of the changes in the electron-nucleus attraction and the electron- electron repulsion?

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The acidity of the group 16 hydrides increase going down the group (H2O << H2S <...

The acidity of the group 16 hydrides increase going down the group (H2O << H2S < H2Se < H2Te). Which is the best explanation for this trend?

(A) The electronegativity of the group 16 elements increases going down the group.

(B) The polarizability of the group 16 elements increases going down the group.

(C) The polarity of the X–H bond increases going down the group.

(D) The H–X–H bond angle increases going down the group.

I don't understand what polarizability means in this particular question. Please explain. From what I understand, acidity increases because atomic radius increases down the group and bonds get bigger I suppose so they are easier to break off.

Thank You!

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350.mg of an unknown protein are dissolved in enough solvent to make 5.00mL of solution. The...

350.mg of an unknown protein are dissolved in enough solvent to make 5.00mL of solution. The osmotic pressure of this solution is measured to be 0.296atm at 25.0°C.

Calculate the molar mass of the protein. Be sure your answer has the correct number of significant digits.

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1. Which of the following gases could have the same pressure and temperature? All of the...

1. Which of the following gases could have the same pressure and temperature? All of the containers are rigid and have the same volume.

A.Ne and N2

B.O3 and H2O

C.N2 and O3

D. Ne, N2, and H2O

2. The decomposition of sodium azide (NaN3) is often used to inflate car airbags. A possible balanced chemical reaction for this decomposition reaction is 6 NaN3(s)+ 2 Fe2O3(s) = 3 Na2O2(s) + 4 Fe(s)+ 9 N2 (g). What volume of nitrogen can be produced at 20.0 °C and 1.05 atm from 1.00 mol of NaN3?

3.. The density of the vapor of a volatile organic compound is 0.960 g/L at 0.2434 atm and 225°C. What is the molar mass of this compound?

4. A gas mixture contains 0.0500 moles of H2, 0.0400 moles of CO2, and 0.0325 moles of N2in a 2.00 L flask. If the total pressure in the flask is 1.316 atm, what is the partial pressure of CO2?

*Please help me with these questions. Thank you.

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