1 answer

What fraction of piperazine (perhydro-1,4-diazine) is in each of its three forms (H2A, HA-, A2−) at...

Question:

What fraction of piperazine (perhydro-1,4-diazine) is in each of its three forms (H2A, HA-, A2−) at pH 6.50? The acid dissociation constant values for piperazine are ?a1=4.65×10−6 and ?a2=1.86×10−10.


Answers

pKa1 + pKa2 = 14

Ka1 = 4.65 x 10^-6

Ka2 = 1.86 x 10^-10

pH = 6.50

[H+] = 3.16 x 10^-7 M

[H+]^2 = 1.0 x10^-13

Ka1 Ka2 = 8.65 x 10^-16

Ka1 [H+] = 1.47 x 10^-12

[H+]^2 + Ka1 Ka2 + Ka1 [H+]   = 1.571 x 10^-12

phphpn0TL.pngH2A = [H+]^2 / [H+]^2 + Ka1 Ka2 + Ka1 [H+]

phpFRUPWL.pngH2A = 0.0636

phpyzKGoJ.pngHA- = Ka1 [H+] / [H+]^2 + Ka1 Ka2 + Ka1 [H+]   

phpC2X1zS.pngHA- = 0.936

phpCUFHKz.pngA2- = Ka1 Ka2 / [H+]^2 + Ka1 Ka2 + Ka1 [H+]

phplMtjDP.pngA2- = 5.51 x 10^-4

.

Similar Solved Questions

1 answer
Please answer both of the following questions: Price мC ATC AVC В A Quantity/Week Refer to...
Please answer both of the following questions: Price мC ATC AVC В A Quantity/Week Refer to the above figure. The competitive firm's short run supply curve starts at B and goes along the ATC curve as quantity increases. starts at B and goes along the MC curve as quantity increases. s...
1 answer
Requierments: 1- General Journal 2-Ledger accounts 3-unadjusted trial balance 4-adjusted trial balance 5-Income Statement 6-retained earnings...
Requierments: 1- General Journal 2-Ledger accounts 3-unadjusted trial balance 4-adjusted trial balance 5-Income Statement 6-retained earnings statement 7-Statement of Financial position 8-Post-closing trial balance A DuVery Ahmed and Ali, had saved some cash and decided to start a Small Delivery ...
1 answer
Calculate the mass of #KCl# that should be dissolved to form a 5 ppm #Cl^-# ion solution having a total volume of 20 #dm^3#?
Calculate the mass of #KCl# that should be dissolved to form a 5 ppm #Cl^-# ion solution having a total volume of 20 #dm^3#?...
1 answer
Part A Daily calorie needs include O BMR, TEF, and calories burned during physical activity. OBMR...
Part A Daily calorie needs include O BMR, TEF, and calories burned during physical activity. OBMR and calories burned during physical activity. O TEF and BMR O TEF and calories burned during physical activity Request Answer Provide Feedback...
1 answer
A photographer in a helicopter ascending vertically at a constant rate of 1.2 m/s accidentally drops...
A photographer in a helicopter ascending vertically at a constant rate of 1.2 m/s accidentally drops a camera out the window when the helicopter is 47.0 m above the ground. (a) How long will it take the camera to reach the ground?...
1 answer
6 ! Required information [The following information applies to the questions displayed below.] Part 2 of...
6 ! Required information [The following information applies to the questions displayed below.] Part 2 of 2 0.5 points During April, the first production department of a process manufacturing system completed its work on 300,000 units of a product and transferred them to the next department. Of these...
1 answer
STS Some updates Homework: Lecture 2 Homework Score: 0 of 1 pt Hep D. Working E....
STS Some updates Homework: Lecture 2 Homework Score: 0 of 1 pt Hep D. Working E. Sleeping O A. Students spend the majorty of their Sime on socialiring or recreation, but heir time on atending class or studying on sleeping....
1 answer
How are euglenas similar to plants?
How are euglenas similar to plants?...
1 answer
How can physics help us understand how the universe began?
How can physics help us understand how the universe began?...
1 answer
Finance Loan 1 Loan 2 Loan 3 Loan 4 Initial Interest Rate Loan Maturity (years) 20...
finance Loan 1 Loan 2 Loan 3 Loan 4 Initial Interest Rate Loan Maturity (years) 20 20 20 % Margin Above Index 3% 3% N/A 3% Adjustment Interval 1 yr. 1 yr. N/A 1 yr. Points 1% 1% 1% 1% Interest Rate Cap None 3%/yr. 1%/yr. N/A Which loan is an unrestricted ARM? Loan 1 Loan 2 Loan 3 O Loan 4...
1 answer
E5.9 (LO 5) Financial Statement Presented below is information for Kaila Company for the month of...
E5.9 (LO 5) Financial Statement Presented below is information for Kaila Company for the month of March 2020. Cost of goods sold $215,000 Rent expense $ 30,000 Freight-out 7,000 Sales discounts 8,000 Insurance expense 6,000 Sales returns and allowances 13,000 Salaries and wages expense 58,000 Sales ...
1 answer
You roll two dice. What is the probability that the sum of the dice is greater than 8 and that one of the dice shows a 6?
You roll two dice. What is the probability that the sum of the dice is greater than 8 and that one of the dice shows a 6?...
1 answer
1. Let A be the surface area of a cube with side s at time t....
1. Let A be the surface area of a cube with side s at time t. a) If the side changes at a rate of 3.0 cm/min, at what rate is the cube's surface area changing when the side is 25 cm? b) If the side changes at a rate of -5.0 cm/min, what is the side of the cube when the surface area is changing a...
1 answer
4. (1.5 pts)You are practicing designing primers that you can use in PCR reactions. You want...
4. (1.5 pts)You are practicing designing primers that you can use in PCR reactions. You want your primers to allow you to amplify the sequence found below. 5°-АсттсслтАTстсТАЛААТА...
1 answer
Provide all of the possible resonance structures for the below shown enolates.
Provide all of the possible resonance structures for the below shown enolates....
1 answer
QUESTION Locate the Centroid of figure 1. 1250mm 020mm 350mm R 150mm 15mm 010mm 10mm 25mm...
QUESTION Locate the Centroid of figure 1. 1250mm 020mm 350mm R 150mm 15mm 010mm 10mm 25mm Figure 1: Gasket plane Prepared by Henry Noweto (2020)...
1 answer
Which of the following correctly identifies the Fisher equation? Multiple Choice r= (1 + R)/(1+1 r=R/...
Which of the following correctly identifies the Fisher equation? Multiple Choice r= (1 + R)/(1+1 r=R/ (1+1 1 + r = R/(1+) 1+r= (1 + R)/(1+1...