Question

Indicator Range(s)
Bromocresol green
Bromothymol blue
Methyl yellow
Red cabbage
Alizarin yellow
Phenolphthalein

From the list above, what is the best indicator for observing pH changes for the following pHs?
pH Best Indicator
pH =2
pH = 4
pH = 6
pH = 8
pH = 10
pH = 12

Answer 1

I NEED HELP @apoorvk pleaseeeeeee :D

Answer 2

@Callisto help please!!

Answer 3

Perhaps Ms. @Callisto would be able to help you out. I suck at chemistry.

Answer 4

HCl 0.1M
Test tube# bromothymol blue methyl yellow bromocresol green red cabbage
1 light green red yellow red
2 light green red yellow red
3 light green yellow yellow red
4 light green yellow green light purple
5 light green yellow blue light purple
6 light green yellow dark purple light purple
7 light blue yellow dark purple light purple


NaOH 0.1 M
Test tube # bromothymol blue red cabbage alizarin yellow phenolphthalein
1 dark purple aqua blue red light purple
2 dark purple aqua blue yellow light purple
3 dark purple aqua blue yellow light purple
4 dark purple aqua blue yellow light purple
5 dark purple dark purple yellow transparent
6 dark purple light purple yellow transparent
7 aqua blue light purple yellow transparent

Calculations/Interpretations: Show all math performed (label the calculation or give the formula, show your setup, and give the result), include proper labels, and/or answer any questions listed below

*Note: You began with 5 ml of 0.1 M HCl and diluted it with 5 ml of water. To determine how many moles of HCl were in that original sample, use the formula moles = molarity x liters. Take the number of moles in that sample and divide it by the number of liters of water in which it was dissolved in test tube 1 (moles/liters = molarity). This gives you the molarity (concentration) of test tube 1. As you moved from test tube 1 through test tube 7, you took 1 ml from the first test tube and 9 ml of water. Therefore, each successive test tube has one tenth as many moles of HCl as the one before it. You will need to find the molarity of test tubes 2 through 7. Use the formula moles /liters = molarity for each test tube.

Sample Calculations:
Test Tube #1
0.1 moles/1000 mL = x moles/5 mL
x = 0.0005 moles
Molarity = 0.0005 moles/0.010 L = 0.05 M
pH = -log[H+] = -log (0.05) = 1.3

Test Tube #2
0.05 moles/1000 mL = x moles/1 mL
x = 0.00005 moles
Molarity = 0.00005 moles/0.010 L = 0.005 M


HCl 0.1 M
Test tube # concentration (M) pH
1 0.05 1.3
2 0.005 2.3
3 0.0005 3.3
4 0.00005 4.3
5 0.000005 5.3
6 0.0000005 6.3
7 0.00000005 7.3

NaOH 0.1 M
Test tube # concentration (M) pOH pH
1 0.05 1.3 1.3
2 0.005 2.3 2.3
3 0.0005 3.3 3.3
4 0.00005 4.3 4.3
5 0.000005 5.3 5.3
6 0.0000005 6.3 6.3
7 0.00000005 7.3 7.3

Answer 5

this is the background info^^
the question is the one on topp^^^^^^^^^^^^^

Answer 6

This-is-mammoth. O.O

Answer 7

@maheshmeghwal9 help!

Answer 8

Sorry dude I m very dull at chem:(

Answer 9

:c

Answer 10

The basic principle of choosing a pH indicator is that the indicator can give you sharp colour change at a certain pH..
There are too many data there and we really need to rearrange it...

Answer 11

I see that there is a column in your question called 'Range(s) ' but with no information provided. What's that?

Answer 12

thats what i need to fill in

Answer 13

Two attachments from.
May be they come of some help:)

Answer 14

thanks:D

Answer 15

yw:)

Answer 16

Have you done that calculation part?

Answer 17

*the

Answer 18

um no. i dontthink so

Answer 19

Do you know how to do the calculation part?

Answer 20

no i dont

Answer 21

How can we help you?

Answer 22

i need to know how to do this above :c ^^^^^^^^^^^^^^^^^^^^^^^^^^at the top

Answer 23

http://en.wikipedia.org/wiki/PH_indicator

May be of help:)

Answer 24

Okay, @maheshmeghwal9 is helping you :)

Answer 25

THANK YOU!!!

Answer 26

How do i do the next part?

From the list above, what is the best indicator for observing pH changes for the following pHs?
pH Best Indicator
pH =2
pH = 4
pH = 6
pH = 8
pH = 10
pH = 12

Answer 27

sorry dude I don't understand the second:(

Answer 28

part*

Answer 29

Extremely sorry for unable to help.

Answer 30

i got it:d thanks for the help:D

Answer 31

how did you find the second part? @seashell