7778-44-1 Usage
Uses
Used in Agriculture:
Calcium arsenate is used as an insecticide and molluscicide for controlling certain insects affecting field crops, particularly cotton. However, it cannot be used safely on apples, peaches, beans, and some other crops due to its burning effect on the foliage and fruit.
Used in Wood Treatment:
Calcium arsenate is also used in weather-resistant wood treatment, mainly in viticulture in the past. It was primarily used against the boll weevil in cotton cultivation.
Used in Viticulture:
In the past, calcium arsenate was used in viticulture for pest control, particularly against the boll weevil in cotton cultivation.
Preparation
An old method involving electrolysis in solution for
the manufacture of calcium arsenate is as follows.
A solution of arsenious oxide in caustic soda
(As2O3:NaOH=198:250) is electrolyzed between iron
electrodes. Hydrogen and a small quantity of metallic
arsenic are liberated at the cathode and very little
oxygen at the anode, the basic arsenite in solution being
oxidized to arsenate. When this oxidation is complete,
any arsenic is filtered off and the solution treated with
milk of lime. A basic arsenate of extremely low solubility
is precipitated and after removal, is washed and dried.
Air & Water Reactions
Slightly soluble in water.
Reactivity Profile
Has only weak oxidizing power but redox reactions can still occur. Soluble in dilute acids. [Hawley]. Produces toxic fumes of arsenic when heated to decomposition .
Hazard
Toxic by ingestion and inhalation.
Health Hazard
CALCIUM ARSENATE is extremely toxic; the probable oral lethal dose for humans is 5-50 mg/kg, or between 7 drops and 1 teaspoonful for a 150 lb. person. It is an irritant to eyes, respiratory tract, mouth and stomach. Damage to kidneys, liver and the nervous system have been reported. (Non-Specific -- Arsenic) Chronic exposure can cause bone marrow damage, often leading to aplastic anemia. There is epidemiological evidence that chronic ingestion of arsenic compounds causes a predisposition to skin cancers.
Fire Hazard
Fire may produce irritating or poisonous gases. When heated to decomposition, CALCIUM ARSENATE produces toxic fumes of arsenic. Avoid heat. Hazardous polymerization may not occur.
Safety Profile
Confirmed human
carcinogen. Poison by ingestion. Moderately
toxic by skin contact. When heated to
decomposition it emits toxic fumes of
arsenic.
Check Digit Verification of cas no
The CAS Registry Mumber 7778-44-1 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 7,7,7 and 8 respectively; the second part has 2 digits, 4 and 4 respectively.
Calculate Digit Verification of CAS Registry Number 7778-44:
(6*7)+(5*7)+(4*7)+(3*8)+(2*4)+(1*4)=141
141 % 10 = 1
So 7778-44-1 is a valid CAS Registry Number.
InChI:InChI=1/2AsH3O4.3Ca/c2*2-1(3,4)5;;;/h2*(H3,2,3,4,5);;;/q;;3*+2/p-6
