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1.06246

1-Naphtholphthalein

pH indicator

Synonym(s):

1-Naphtholphthalein

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Size/SKUAvailabilityPrice
1 g
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$342.00
5 g
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$389.00
100 g
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$3,420.00

About This Item

Empirical Formula (Hill Notation):
C28H18O4
CAS Number:
Molecular Weight:
418.44
UNSPSC Code:
12352115
EC Index Number:
209-875-5
NACRES:
NA.21
MDL number:

$342.00


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Product Name

1-Naphtholphthalein, indicator

Quality Segment

form

solid

loss

≤5% loss on drying, 110°C

visual transition interval

7.1-8.3, pink-brown to blue

mp

253-255 °C

bulk density

350 kg/m3

Amax

470-485 nm (buffer pH 7.1), 649-654 nm (buffer pH 8.3)

storage temp.

2-30°C

SMILES string

O1C(c6c(cccc6)C1=O)(c4c5c(c(cc4)O)cccc5)c2c3c(c(cc2)O)cccc3

InChI

1S/C28H18O4/c29-25-15-13-23(17-7-1-3-9-19(17)25)28(22-12-6-5-11-21(22)27(31)32-28)24-14-16-26(30)20-10-4-2-8-18(20)24/h1-16,29-30H

InChI key

HQHBAGKIEAOSNM-UHFFFAOYSA-N

Analysis Note

Identity (UV/VIS-Spectrum): passes test
Transition range: pH 7.1 - pH 8.3pinkbrownish - blue
Absorption maximum λ 1 (buffer pH 7.1): 470 - 485 nm
Absorption maximum λ 2 (buffer pH 8.3): 649 - 654 nm
Spec. Absorptivity A 1%/1cm (λ1max; 0.01 g/l; buffer pH 7.1; calc. on anhydrous substance): 100 - 180
Spec. Absorptivity A 1%/1cm (λ2max; 0.01 g/l; buffer pH 8.3; calc. on anhydrous substance): 360 - 520
Loss on drying (110 °C): ≤ 5 %


Storage Class

11 - Combustible Solids

WGK

WGK 3

Flash Point (°F)

Not applicable

Flash Point (°C)

Not applicable



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