. Mg2+ ions are present in seawater, and the metal is often prepared by "harvesting" these ions and converting them to neutral Mg metal. The average magnesium content of the oceans is about 1270 g Mg2+ per ton of seawater, and the density of seawater is about 1.02 g/mL. (Some additional unit conversion factors are given below.) 1 ton = 2000 pounds 1 gallon = 3.7854 L 454 g = 1 pound

(6 pts) (a). How many gallons of seawater would be required to supply 123 kg of magnesium?

(6 pts) (b). Use information from above to find the molarity of Mg2+ ions in seawater?

Determine how many micrograms of phosphorus are in the following solutions:

1. 0.02M KH₂PO₄

2. 0.3M KH₂PO₄

3. 0.5M KH₂PO₄

4. 0.8M  KH2PO4

5. 1M  KH2PO4

6. 1.3M KH₂PO₄

When 2.14 g of a nonelectrolyte solute is dissolved in water to make 165 mL of solution at 22 °C, the solution exerts an osmotic pressure of 821 torr.

Compute the volume of 0.20M silver nitrate needed to precipitate the chloride ion in a 0.60g sample of an unknown that is 45% chloride and the mass of the solid nitrate used to prepare such a solution.

Mercury ions (Hg2+2) can be removed from solution by precipitation with Cl−. Suppose that a solution contains aqueous Hg2(NO3)2.

Express your answer as a chemical equation. Identify all of the phases in your answer.

A)Write complete ionic equation to show the reaction of aqueous Hg2(NO3)2 with aqueous sodium chloride to form solid Hg2Cl2 and aqueous sodium nitrate.

B)Write net ionic equation to show the reaction of aqueous Hg2(NO3)2 with aqueous sodium chloride to form solid Hg2Cl2 and aqueous sodium nitrate.

1) Explain with halogens are deactivators, but ortho, para directors, instead of m directors, in an EAS reaction.

2) Draw the energy diagrams for the first step of an electrophilic aromatic substitution reactions of a monosubstituted benzene, when the substituent is an electron-withdrawing group (E), an electron-donating group (D), and a halogen (X), respectively.

You measure the pH of rainwater at 5.4. Calculate the partial pressure of carbon dioxide (assume only CO₂ is present).

PLEASE BE VERY CLEAR WITH WHERE EVERYTHING COMES FROM

Which substances given below produce a basic solution when dissolved in water?

NaCl

KOH

Sucrose

NH3

Vinegar

Suppose an everyday chemical reacts with vinegar. Is the substance more likely to be an acid or a base? Justify your answer.

A 25.0 mL sample of 0.30 M HCOOH is titrated with 0.20 M KOH. What is the pH of the solution after 25.0 mL of KOH has been added to the acid? Ka = 1.8x10^-4

Determine the electron geometry, molecular geometry, and idealized bond angles for each of the following molecules. In which cases do you expect deviations from the idealized bond angle?

CF4

NF3

OF2

H2S

Given that the density of air at 0.987 bar and 27°C is 1.146 kg m⁻³, calculate the mole fraction and partial pressure of nitrogen and oxygen assuming the following conditions.

(a) air consists only of these two gases
mole fraction nitrogen
  
mole fraction oxygen
  
partial pressure nitrogen
  bar
partial pressure oxygen
  bar

(b) air also contains 1.0 mole percent Ar
mole fraction nitrogen
  
mole fraction oxygen
  
partial pressure nitrogen
  bar
partial pressure oxygen
  bar
partial pressure argon
  bar

1.) What is the pH of a solution created by combining 1.34 mole of HOBr and 0.47 mole NaOH in a 1.00L solution? K_{a HOBr} = 2.5 x 10<sup>-9

2.)</sup> What is the pH after 0.24 moles of NaOH is added to a buffer containing 1.00 moles of NH₃ and 1.00 moles NH₄Cl ? K_{b NH3} = 1.8 x 10<sup>-5

3.)</sup> What is the pH of a buffer made by combining 0.69 moles HOBr with 0.65 moles NaOBr in a 100.00mL solution? K_{a HOBr} = 2.5 x 10^-9

A 100 g piece of copper, initially at 95,0 C ,
is dropped into 200 g of water. If initial temperature of
water is 1 5 C, what is final temperature of the system, if the heat lost to surounding is ignored

please, step by step solution.

Physical Chemistry:

Calculate ΔG for the isothermal compression of 10.0 g of water from 1.0 atm to 100.0 atm at 25°C

What is the total enthalpy change when 100.0 g of solid NH3 at -150.0 degrees Celcius is changed to gas at 100 degrees Celcius?

I've done this problem several times and keep getting the answer of 223 kj, but in class we were told the correct answer is 237 kj. Please show all your steps/work so I can see what I'm doing wrong. Thank you!