Find the pH during the titration of 20.00 mL of 0.1500 M benzoic acid, C6H5COOH (Ka = 6.3 10-5), with 0.1500 M NaOH solution after the following additions of titrant. (a) 0 mL (b) 10.00 mL (c) 15.00 mL (d) 20.00 mL (e) 25.00 mL

Describe how the retention time of a peak is calculated if dichloromethane is injected with the sample

Ethanol (C2H5OH) is a very important chemical.in addition to being widely used as an industrial solvent,a gasoline additive,and an alternative fuel,it is well known as the alcoholic beverages.A common name for ethanol is grain alcohol because it is formed by the fermentation of glucose (C6H12O6) and other sugars in grains such as corn,wheat and barley:
C6H12O6---'C2H5OH + CO2
The previous reaction has been carried out for many centuries and is one of the oldest manufacturing processes.In a more recent development,ethanol can be prepared by reacting ethylene (found in petroleum) with water:
C2H4 +H2O ---C2H5OH
a.write the balanced equation for each of the two reactions above
b.Calcute the % A.E ( for the product ethanol) for the two reactions.
c.Explain how you can determine which reaction has the higher atom economy without doing the calculation in part (b) above .
d.Is either method sustainable?Which one? justify your answer.
e.Given the result from parts (b) and (d) above ,select one of the two methods as the better candidate overall for preparing ethanol.justify your selection.

There are two possible methods for recovering copper from a solution of copper (II) sulfate, one uses precipitation and the other uses redox.

(a) Copper(II) ions can be precipitated as copper(II) carbonate.

CuSO₄(aq) + Na₂CO₃(aq) → CuCO₃(s) + Na₂SO₄(aq)

How many mL of 0.144 M Na₂CO₃ would be needed to precipitate all of the copper ions in 25.5 mL of 0.165 M CuSO₄? How many grams of CuCO₃ could be recovered? (Include units in your answer. More information.)

(b) Copper(II) ions can be displaced by aluminum metal.

3 CuSO₄(aq) + 2 Al(s) → Al₂(SO₄)₃(aq) + 3 Cu(s)

How many grams of Al would be needed to displace all of the copper ions in 25.5 mL of 0.165 M CuSO₄? How many grams of Cu could be recovered? (Include units in your answer. More information.)

Please be very specific with the answers!! I only have one submission left and im very lost!

Part A

Aspirin (acetylsalicylic acid, C9H8O4) is a weak monoprotic acid. To determine its acid-dissociation constant, a student dissolved 2.00 g of aspirin in 0.600 L of water and measured the pH. What was the Ka value calculated by the student if the pHof the solution was 2.62?

Express your answer numerically using two significant figures.

Part B

A 0.100 M solution of ethylamine (C2H5NH2) has a pH of 11.87. Calculate the Kb for ethylamine.

Express your answer numerically using two significant figures.

Analyze the reactions below and determine which of them has the largest relative increase in entropy? Circle your choice and explain your answer qualitatively.

CO (g) + 3 H2 (g) <---> CH4 (g) + H2O (G)

C (s) + H2O (g) <---> CO (g) + H2 (g)

CH4 (g) + Cl (g) <----> CH3Cl (g) + HCl (g)

Complete and Balance each reaction in molecular, ionic, and net ionic form:

1. AgNO3(aq) + K2CrO4(aq) ---->

Ionic:

Net Ionic:

2. Ba(NO3)2(aq) + (NH4)3PO4(aq) ---->

Ionic:

Net Ionic:

3. NaHCO3(aq) + H3PO4(aq) ----->

Ionic:

Net Ionic:

Consider the following molecules or ions: ClO2+ , AsF6 - , IOF3,  and SOF2. Answer the following questions based on the Lewis structures and VSEPR theory prediction of their molecular shapes.

(a) Which one has only bond angles of 109.5°?

(b) Which one has only bond angles of 120°?

(c) Which one has bond angles of 90 and 180°?

(d) Which one has bond angles of 90, 120, and 180°?

1. Write a balanced chemical equation to describe the combustion reaction of methane (CH₄). Use standard enthalpies of formation to calculate the ΔH_rxn for the equation you wrote. If you burn enough methane to produce 1.6 × 10³ kJ of heat energy, how many liters of CO₂ would be produced at STP?

Gaseous methane will react with gaseous oxygen to produce gaseous carbon dioxide and gaseous water. Suppose 15.7 g of methane is mixed with 34. g of oxygen. Calculate the maximum mass of carbon dioxide that could be produced by the chemical reaction. Be sure your answer has the correct number of significant digits.

A water sample contains 150 mg/L ethylene glycol (C2H6O2) and 200 mg/L phenol (C6H6O). Calculate the COD and TOC.

After 1.60 mol of NH3 gas is placed in a 1600-cm^3 box at 25 degrees C, the box is heated to 500 K. At this temperature, the ammonia is partially decomposed to N2 and H2, and a pressure measurement gives 4.85 MPa. Find the number of moles of each component present at 500 K.