Unhed States .
EnvuQmncnt&l ProtcctioD
As
Office of Pollution
Prevention and Toxics
Washington, DC 20460
Revised May 1996
EPA745-R-96-004
TOXICS RELEASE INVENTORY
List of Toxic Chemicals within the Water Dissociable Nitrate
Compounds Category and Guidance for Reporting
Section 313 of the Emergency Planning and Community Right-to-Know Act of 1986
(EPCRA) requires certain facilities manufacturing, processing, or otherwise using listed toxic
chemicals to report their environmental releases of such chemicals annually. Beginning with the
1991 reporting year, such facilities also must report pollution prevention and recycling data for
such chemicals, pursuant to section 6607 of the Pollution Prevention Act, 42 U.S.C. 13106.
When enacted, EPCRA section 313 established an initial list of toxic chemicals that was
comprised of more than 300 chemicals and 20 chemical categories. EPCRA section 313(d)
authorizes EPA to add chemicals to or delete chemicals from the list, and sets forth criteria for
these actions.
CONTENTS
Section 1. Introduction 2
1.1 Who Must Report 2
1:2 Thresholds . 2
.1.3 Chemicals within the Water Dissociable Nitrate Compounds Category 3
1.4 DeMinimis Concentrations - 3
Section 2. Guidance for Reporting Chemicals within the Water Dissociable Nitrate
Compounds Category 4
2.1. Chemicals within the Water Dissociable Nitrate Compounds Category 4
2.2. Determining Threshold .and Release Quantities for Nitrate Compounds4
2.3. Reporting Nitrate Compounds Generated from the Partial or Complete
Neutralization of Nitric Acid 5
2.3.1. Estimating Nitric Acid Releases 6
2.3.2. Estimating Treatment Efficiencies for Nitric Acid Neutralization ... 7
2.3.3. Estimating Releases of Nitrate Compounds Generated from the
Neutralization ofNitric Acid 9
2.4. Generation of Nitrate Compounds from Biological Wastewater
Treatment 10
Section 3. CAS Number List of Some of the Individual Chemicals within the Water
Dissociable Nitrate Compounds Category 11
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Section 1. Introduction
On November 30,1994 EPA added 286 chemicals and chemical categories, which include
39 chemicals as part of two delineated categories, to the list of toxic chemicals subject to
reporting under section 313 of the Emergency Planning and Community Right-to-Know Act of
1986 (EPCRA), 42 U.S.C. 11001. These additions are described at 59 FR 61432, and are
effective January 1, 1995 for reports due July 1, 1996. Six chemical categories (nicotine and
salts, strychnine and salts, polycyclic aromatic compounds, water dissociable nitrate compounds,
diisocyanates, and polychlorinated alkanes) are included in these additions.. At the time of the.
addition, EPA indicated that the Agency would develop, as appropriate, interpretations and
guidance that the Agency determines are necessary to facilitate accurate reporting for these
categories. This document constitutes such guidance for the water dissociable nitrate compounds
category.
Section 1.1 Who Must Report'
A plant, factory, or other facility is subject to the provisions of EPCRA section 313, if it
meets aU three of the following criteria:
It conducts manufacturing operations (is include in Standard Industrial
Classification (SIC) codes 20 through 39); and
It has 10 or more full-time employees (or the equivalent 20,000 hours per year);
It manufacturers, imports, processes, or otherwise uses any of the toxic chemicals
listed on the EPCRA section 313 list in amounts greater than the "threshold"
quantities specified below.
Section 1.2 Thresholds
Thresholds are specified amounts of toxic chemicals used during the calendar year that
trigger reporting requirements.
If a facility manufactures or imports any of the listed toxic chemicals, the threshold
quantity will be:
25,000 pounds per toxic chemical or category over the calendar year.
If a facility processes any of the listed toxic chemicals, the threshold quantity will be:
25,000 pounds per toxic chemical or category over the calendar year.
If a facility otherwise uses any of the listed toxic chemicals (without incorporating it into
any product or producing it at the facility), the threshold quantity is:,
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10,000 pounds per toxic chemical or category over the calendar year.
EPCRA section 313 requires threshold determinations for chemical categories to be based
on the total of all chemicals in the category manufactured, processed, or otherwise used. For
example,- a facility that manufactures three members of a chemical category would count the total
amount of all three chemicals manufactured towards the manufacturing threshold for that
category. When filing reports for chemical categories, the releases are determined in the same
manner as the thresholds. One report is filed for the category and all releases are reported on this
form.
Section 1,3 Chemicals within the Water Dissociable Nitrate Compounds Category
EPA is providing a list of CAS numbers and chemical names to aid the regulated
community in determining whether they need to report for the water dissociable nitrate
compounds category. The list includes individual chemicals within the water dissociable nitrate
compounds category. If a facility is manufacturing, processing, or otherwise using a chemical
which is on this list, they must report this chemical. However, this list is not exhaustive. If a
facility is manufacturing, processing, or otherwise using a water dissociable nitrate compound,
they must report the chemical, even if it does not appear on the list.
Section 1.4 DeMinimis Concentrations
The water dissociable nitrate compounds category is subject to the one percent de minimis
concentration. Thus, mixtures that contain members of this category in excess of the de minimis
should be factored into threshold and release determinations.
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Section 2. Guidance for Reporting Chemicals within the Water Dissociable Nitrate.
Compounds Category
Note: for the purposes of reporting under the nitrate compounds category, water
dissociable means that the nitrate ion dissociates from its counterion when in solution.
Section 2.1 Chemicals within the Water Dissociable Nitrate Compounds Category
Chemicals within the nitrate compounds category are only reportable when in aqueous
solution. All water dissociable nitrate compounds are included in the nitrate compounds category,
including ammonium nitrate. Specifically listed section 313 chemicals are not included in
threshold determinations for chemical categories such as the water dissociable nitrate compounds
'category. Specifically listed toxic chemicals are subject to their own individual threshold
determinations. As of December 1, 1994, ammonium nitrate (solution) is not an individually listed
chemical on the EPCRA section 313 list. However, ammonium nitrate is still subject to reporting
under the nitrate compounds category. In addition, the aqueous ammonia from the dissociation
of ammonium nitrate when in aqueous solution is subject to reporting under the ammonia listing.
Section 2.2 Determining Threshold and Release Quantities for Nitrate Compounds
The total nitrate, compound, including both the nitrate ion portion and the counterion, is
included in the nitrate compounds category. When determining threshold amounts, the total
weight of the nitrate compound is to be included in all calculations. However, only the nitrate ion
portion is to be included when determining the amount of the chemicals within the nitrate
compounds category that is released, transferred, or otherwise, managed in wastes.
.Example 1: In a calendar year, a facility processes 100,000 pounds of ammonium nitrate
(NH4NO3), i/i aqueous solution; which is released to waste water streams then transferred to a
POTW. The quantity applied towards threshold calculations for the nitrate compounds
category is the total quantity of the nitrate compound or 100,000 pounds. Since this quantity
exceeds the 25,000 pound processing, threshold, the facility is required to report for the nitrate
compounds category. Under the nitrate compounds category, only the weight of the nitrate
ion portion of ammonium nitrate is included in release and transfer calculations. The
molecular weight of ammonium nitrate is 80.04 and the weight of the nitrate ion portion is
62.01 or 77.47 percent of the molecular weight of ammonium nitrate. Therefore, the amount
of nitrate ion reported as transferred to the POTW is 77.47 percent of 100,000 pounds or
77,470 pounds (reported as 77,000 pounds). The aqueous ammonia from ammonium nitrate
is reportable under the EPCRA Section 313 listing for ammonia. For determining thresholds
and calculating releases under the ammonia listing, see the separate directive, Guidance for
Reporting Aqueous Ammonia (EPA document #745-R-95-003, July. 1995). "
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Example 2: In a calendar year, a facility manufactures as by-products 20,000 pounds of
sodium nitrate (NaNO3) and 10,000' pounds of calcium nitrate (CaCNOj)^, both in aqueous
solutions, and releases these solutions to wastewater streams. The total quantity of nitrate
compounds manufactured by the facility is the sum of the two chemicals, or 30,000 pounds,
which exceeds the manufacturing threshold quantity of 25,000 pounds. The facility therefore
is required to report for the nitrate compounds category. By weight, the nitrate ion portion is
72.96 percent of sodium nitrate and is 75.57 percent of calcium nitrate. Of the 20,000 pounds
of the sodium nitrate in solution, 72.96 percent or 14,592 pounds is nitrate ion, and similarly,
of the 10,000 pounds of the calcium nitrate in solution, 75.57 percent or 7,557 pounds is
nitrate ion. The total nitrate ion in aqueous solution released by the facility is the sum of the
nitrate ion in the two solutions or 22,149 pounds (reported as 22,000 pounds). _
Section 2.3 Reporting Nitrate Compounds Generated from the Partial or Complete
Neutralization of Nitric Acid
Nitric acid is an individually listed chemical on the original EPCRA section 313 list and is
reported as a separate chemical if the manufacture, process or otherwise use thresholds are
exceeded. The partial or. complete neutralization of nitric acid results in the formation of nitrate
compounds which are reported as chemicals within the nitrate compounds category if their
manufacture, process or otherwise use thresholds are exceeded.
Mineral acids such as nitric acid may be present in aqueous waste streams that are sent to
on-site neutralization or are discharged to a publicly owned treatment works (POTW) or other .
off-site treatment facility. As stated in the Toxic Chemical Release Inventory Reporting Form R
and Instructions document (revised 1993 version, EPA 745-K-94-001),. on-site acid neutralization
and its efficiency must be reported in Part n, section 7A of Form R (waste treatment methods and
efficiency section). For purposes of reporting on Form R, EPA-considers a waste mineral acid at
a pH 6 or higher to be 100 percent neutralized (water discharges to receiving streams or POTWs
are reported as zero). The nitrate compounds produced from the complete neutralization (pH 6.0
or above) of nitric acid are reportable under the nitrate compounds category and should be
included in all threshold and release calculations. Two Form R reports'would be required if the
manufacture, process or otherwise use thresholds are exceeded for nitric acid and for the nitrate
compounds category.
If the nitric acid treatment efficiency is not equal to 100 percent (pH is less than 6), the
amount of the acid remaining in the waste stream which is released to the environment on-site or
off-site must be reported in Part n of Form R. The nitrate compounds produced from the partial
neutralization of nitric acid are reportable under the nitrate compounds category and should be
included in all threshold and release calculations. Two reports would again be required if the
manufacture, process or otherwise use thresholds are exceeded for nitric acid and for the nitrate
compounds category.
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Section 2.3.1 Estimating Nitric Acid Releases
The pH of the waste stream can be used to calculate the amount of nitric acid in the
stream and the efficiency of neutralization. The pH is a measure of the acidity or alkalinity of a
waste stream and can be obtained readily using a pH meter or pH sensitive paper. The pH scale
itself varies from 0 to 14.
The total nitric acid concentration (ionized and un-ionized) in pounds/gallon can be
calculated by using the pH value of the solution, the molecular weight and ionization constant of
the acid, and appropriate conversion factors. The total acid concentration for nitric acid for
different pH values is listed in Table 1. The calculation of mineral acid concentrations and the
derivation of Table 1 are discussed in a separate directive, Estimating Releases for Mineral Acid
Discharges Using pH Measurements, and .in an addendum to this directive.
The procedure outlined in this guidance document for calculating the quantity of nitrate
compounds formed from the complete or partial neutralization of nitric acid can be used if nitric
acid is the only mineral acid hi a solution. In addition, the calculation of nitric acid releases using
only pH measurements is a rough estimate. The subsequent -calculation of nitrate compound
releases is therefore also only a rough estimate. The estimates can be made for a waste stream
with a steady pH below 6 or for one whose pH temporarily drops to below pH 6. Facilities
should use their best engineering judgement and knowledge-of the solution to evaluate how
reasonable the estimates are.
Example3: In a calendar year, a facility transfers 1.0 million gallons of a.solution containing
nitric acid (HNO3), at pH 4, to a POTW. Using Table 1 (next page), a pH of 4 corresponds to
a concentration of 0.0000520 Ibs HNO3/gallon of solution. The weight of HNQ3 transferred
can be estimated using the equation:
Transfer of HNO, = (concentration of HNO3) x (effluent flow .rate)
Substituting the example values into the above equation yields:
Transfer of HNO, = O.OOOQ520 Ibs/gal HNO, x 1.000.000 gal solution/yr = 52 Ibs/yr
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Example 4: A facility had an episodic release of nitric acid (HNO3) in which the waste stream
was temporarily below pH 6. During the episode, the. waste-water (pH 2.0) was discharged to
a river for 20 minutes at a rate of 100 gallons per minute. Using Table 1, a pH of 2.0 for
HNO3 represents a concentration of 0.0052000 Ibs HNO3/gallon of solution. The amount of
the HN03 released can be estimated using the following equation:
Release of HNO3 = (concentration of HN03) x (effluent flow rate).
Substituting the example values in the above equation:
Release of HNO, = 0.0052000 Ibs/gal x 100 gal/min x 20 min = 10 Ibs
Table 1. Nitric Acid Concentration Versus pH
pH
0.0
0.2
. 0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
.2.4
2.6
2.8
Nitric Acid Concentration
Gbs/gallon)
. 0.5200000 !
0.3300000
0.2100000
0.1300000
0.0830000
0.0520000
0.0330000
0.0210000
0.0130000 .
0.0083000
0.0052000
0.0033000
0.0021000
0.0013000
0.0008300
pH
3.0
. 3.2
3.4
3.6
3.8
4.0
4.2
4.4
4.6
4.8
5.0
5.2
5.4
5.6
5.8
6.0
Nitric Acid Concentration
(Ibs/gallon)
0.0005200
0.0003300
. 0.0002100
0.0001300
0.0000830
0.0000520
0.000033Q
0.0000210
0^0000130
0.0000083
0.0000052
0.0000033
0.0000021
0.0000013
0.0000008
0.0000005
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Section 2.3.2 Estimating .Treatment Efficiencies for Nitric Acid Neutralization
Nitric acid solutions that are neutralized to a pH of 6 or above have a treatment efficiency
of 100 percent. If nitric acid is neutralized to a pH less than 6, then the reportable treatment
efficiency is somewhere between 0 and 100 percent. It is possible to estimate the neutralization
treatment efficiency using nitric acid concentration values directly from Table 1 in the equation
given below. The concentrations correspond to the pH values before and after treatment.
Treatment Efficiency = (I-E)/I x 100
where I = acid concentration before treatment and
E = acid concentration after treatment
Example 5: A nitric acid (HN03) waste-stream of pH 2.4 is neutralized to pH 4.6. Using
Table 1, the initial nitric acid concentration is 0.0021000 mol/liter and the final concentration
is 0.0000130 mol/liter. Substituting these values into the .equation for treatment efficiency:
Treatment Efficiency - (0.0021000 - 0.0000130)70.0021000 x 100
= 99.4 percent.
For strong acids only (including.nitric acid), the net difference in pH before and after
treatment can be used to estimate the treatment efficiency since pH is directly proportional to the
acid concentration. For example, a pH change of one unit results in a treatment efficiency of 90
percent, whether the pH change is from pH 1 to pH 2 or from pH 4 to pH 5. Table 2 summarizes
treatment efficiencies for various pH changes (the pH change is the difference between the initial
pH and the pH after neutralization). In the table, some pH changes result in the same treatment
efficiency values due to rounding to one decimal place.
Table 2. Nitric Acid Treatment Efficiencies for Various pH Changes
pH Change
1.0
1.1
11 "1.2
1.3
1.4
1.5
Treatment Efficiency (%)
90.0
92.1
93.7
95.0
96.0
96.8
pH Change
2:0
2.1
2.2
2.3
2.4
2.5
'Treatment Efficiency (%)
99.0
99.2
99.4
99.5
99.6
99.7
8
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1.6
1.7
1.8
1.9
97.5 ...
98.0 ' '
98.4
98.7
j
2.6
;
2.7
2.8
2.9
3.0
99.8
99.8
99.8
99.9
99.9
Example 6: If a nitric acid (HNO3) waste stream of pH 2 is treated to pH 4, the pH change is
2 units. Using Table 2 above, the treatment efficiency is given as 99.0 percent.
Section 2.3.3 Estimating Releases of Nitrate Compounds Generated from the Neutralization
of Nitric Acid
The nitrate compounds produced from the complete neutralization (pH 6.0 or above) or
partial neutralization (pH less than 6) of nitric acid are reportable under the nitrate compounds
category if the appropriate threshold is met and should be included in all threshold and release
calculations. In order to determine the quantity of a nitrate .compound generated and released, the
quantity of nitric acid released must be known (or calculated from the'equations used in Examples
3 and 4 above) as well as the nitric acid treatment efficiency (calculated from the equations used
in Examples. 5 and 6 above).
The neutralization of nitric acid will most likely result in the generation of monovalent
nitrate compounds (such as sodium nitrate and potassium nitrate). The quantity .of these
compounds formed in kilomoles will be equal to the quantity of the nitric acid neutralized in
kilomoles. If divalent nitrate compounds are formed (such as calcium nitrate), the quantity of
these compounds formed in kilomoles will be equal to one-half the quantity of the nitric acid
neutralized in kilomoles. Similarly, if trivalent nitrate compounds are formed (such as iron (III)
nitrate), the quantity formed of these compounds in kilomoles will be equal to one-third the
quantity of the nitric acid neutralized in kilomoles. Note: to calculate the releases of nitrate
compounds generated from the neutralization of nitric acid, the molecular weight of the nitrate
compound formed must be used. Molecular weights of some of the individual chemicals within
the water dissociable nitrate compounds category are given in Table 3..
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Example 7: In a calendar year, a facility transfers 50,000 pounds of nitric acid (HNO3) to an
on-site treatment facility. The nitrte acid treatment efficiency is 95 percent, and the nitrate
compound formed as a result of the treatment is sodium nitrate (NaNO3). The quantity of
nitric acid transferred that is neutralized (generating sodium nitrate) is 95 percent of 50,000
pounds or 47,500 pounds. The molecular weight of nitric acid is 63.01. kg/kmol, and the
molecular weight of sodium nitrate is 84.99 kg/kmol. The quantity of nitric acid neutralized is
converted first to kilograms then to kilomoles using the following equations:
Kilograms HNO3 neutralized = (fos HNO3 neutralized) x (0.4536 kg/lb)
Kilomoles HN03 neutralized = (kg HNO3) + (MW of HNO3 in kg/kmol).
Substituting the example values into the above equation yields:
Kilograms HNO3 neutralized = 47,500 Ibs x 0.4536 kg/lb
- 21,546 kg
Kilomoles HNO3 neutralized - 21,546 kg + 63.01 kg/kmol
- 341.9 kmol..
(continued below)
(Example 7, continued)
The quantity of sodium nitrate generated in kilomoles is equal to the quantity of nitric acid
neutralized (341.9 kmol). The quantity of sodium nitrate generated in kilomoles is converted
first to .kilograms then to pounds using the following equations:
Kilograms NaNO3 generated = (kmol NaNO3) x (MW of NaNO3 in kg/kmol)
Pounds NaN03 generated = (kg NaN03) x (2.205 Ibs/kg).
Substituting the values into the above equation yields:
Kilograms NaNO3 generated = 341.9 kmol x 84.99 kg/kmol
= 29,058 kg
Pounds NaNO3 generated = 29,058 kg x 2.205 Ibs/kg
= 64,073 pounds (reported as 64,000 pounds).
The 64,000 pounds of sodium nitrate generated is the quantity used .to determine whether
thresholds have been met.or exceeded. The quantity of nitrate ion released is calculated as in
Example 1 above. . j .
Section 2.4 Generation of Nitrate Compounds from Biological Wastewater Treatment
If a facility treats wastewater on-site biologically, using the activated sludge process, for
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example, the.facility may be generating nitrate compounds as by-products of this biological .
process. The nitrate ion generated from'this process will be associated with various counterions
(e.g. sodium ion, potassium ion). In the absence of information on the identity of the counterion,
a facility should assume for the purposes of EPCRA section 313 threshold determinations that the
counterion is sodium ion.
11
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.Section 3. CAS Number List of Some of the Individual Chemicals within the Water
Dissociable Nitrate Compounds Category
EPA is providing the following 1'rst of CAS numbers and chemical names to aid the
regulated community in determining whether they need to report for the water dissociable nitrate
compounds category. If a facility is manufacturing, processing, or otherwise using a chemical
which is listed below, they must report this chemical. However, this list is not exhaustive. If a
facility is manufacturing, processing, or otherwise using a water dissociable nitrate compound,
they must report this chemical, even if it does not appear on the following list.
Table 3. Listing by CAS Number of Some of the Individual Chei
Compounds Category
Chemical Name
Aluminum nitrate, nonahydrate
Ammonium nitrate
Cerium (III) ammonium nitrate, tetrahydrate
Cerium (IV) ammonium nitrate
Barium nitrate
Beryllium nitrate, trihydrate
Cadmium nitrate
Cadmium nitrate, tetrahydrate
Calcium nitrate
Calcium nitrate, tetrahydrate
Cerium (HI) nitrate, hexahydrate
Cesium nitrate
Chromium (III) nitrate, nonahydrate
Cobalt (TT) nitrate, hexahydrate
Copper (II) nitrate, trihydrate
Copper (II) nitrate, hexahydrate
Dysprosium (III) nitrate, pentahydrate
Erbium (III) nitrate, pentahydrate
Gadolinium (III) nitrate, hexahydrate
Gallium nitrate, hydrate
nicals within the Water Dissociable Nitrate
Molecular Weight*
213.00.
80.04
486.22
548.23
261.34
133.02
236.42
236.42
164.09
164.09
326.13
194.91
238.01
182.94
187.56
187.56
348.51
353.27
343.26
255.73
CAS Number
7784-27-2
6484-52-2
13083-04-0
10139-51-2 .
10022-31-8
7787-55-5
10325-94-7
10022-68-1
10124-37-5
13477-34-4'
10294-41-4
7789-18-6
7789-02-8
10026-22-9
10031-43-3
13478-38-1
10031-49-9
10031-51-3
19598-90-4
69365-72-6
* For hydrated compounds, e.g. aluminum nitrate, nonahydrate, .the molecular weight excludes the weight of the hydrate portion. For
example, the same molecular weight is provided for aluminum nitrate, nonahydrate and aluminum nitrate.
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Table 3 . Listing by CAS Number of Some of the Individual Chei
. Compounds Category
Chemical Name
Iron (III) nitrate, hexahydrate
Iron (III) nitrate, nonahydrate
Lanthanum (III) nitrate, hexahydrate
Lead (II) nitrate
Lithium nitrate
Lithium nitrate, .trihydrate
Magnesium nitrate, dihydrate
Magnesium nitrate, hexahydrate
Manganese (II) nitrate, tetrahydrate
Neodymium (III) nitrate, hexahydrate
Nickel (II) nitrate, hexahydrate
Potassium nitrate
Rhodium (HI) nitrate, dihydrate"
Rubidium nitrate
Samarium (III) nitrate, hexahydrate
Scandium (III) nitrate1
Scandium (III) nitrate, tetrahydrate .'
Silver nitrate
Sodium nitrate
Strontium nitrate
Strontium nitrate, tetrahydrate
Terbium (III) nitrate, hexahydrate .
Thorium (IV) nitrate ' .
Thorium (IV) nitrate, tetrahydrate
Yttrium (HI) nitrate, hexahydrate
Yttrium (TO) nitrate, tetrahydrate
nicals within the Water Dissociable Nitrate
Molecular Weight'
241.86
241.86
324.92
331.21
68.95
68.95
148.31
148.31
178.95
330.25
182.70
101.10
288.92
147.47
336.37
230.97
230.97
169.87
84.99
211.63
211.63
344.94
480.06
/
480.06
274!.92
274.92
CAS Number
13476-08-9
7782-61-8
10277-43-7
10099-74-8
7790-69-4
13453-76-4
15750-45-5
13446-18-9
20694-39-7 .
16454-60-7
13478-00-7
7757-79-1
13465-43-5.
13126-12-0
13759-83-6
13465-60-6
16999-44-3
7761-88-8
7631-99-4
10042-76-9
13470-05-8
13451-19-9 -
13823-29-5
13470-07-0
13494-98-9
13773^69-8
* For hydrated compounds, e.g. aluminum nitrate, nonahydrate, the molecular weight excludes the weight of the hydrate portion. For
example, the same molecular weight is provided for aluminum nitrate, nonahydrate and aluminum nitrate.
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Table 3. Listing by CAS Number of Some of the Individual Chemicals within the "Water Dissociable Nitrate
Sine nitrate, trihydrate '
Molecular Weight*
189.39'
131446-84-9
itrate. hexahydrate
189.39
10196-18-6
339.24
13986-27-1
' For hydrated compounds, e.g. aluminum nitrate, nonahydrate, the molecular weight secludes the weight of the hydrate portion. For
example, the same molecular weight is provided for aluminum nitrate, nonahydrate and aluminum nitrate.
14
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