Оксид празеодима

Description

Praseodymium oxide is an oxide compound of the rare earth element praseodymium. The position is cataloged under CAS number 11113-81-8 and in the original classification is classified under the “Peroxides” section, which is due to the presence of praseodymium in a stable +4 oxidation state and the ability to form non-stoichiometric oxide phases with excess oxygen. The molecular weight on the card is 329.812, which corresponds to the composition Pr₆O₁₁, while the given exact mass of 249.96 corresponds to a different oxygen stoichiometry; the discrepancy reflects the non-stoichiometric nature of praseodymium oxides and is not smoothed out in the description. Praseodymium oxides serve as pigments for glass and ceramics, components of catalysts, and starting material for the production of metallic praseodymium and its compounds.

Basic Attributes

• CAS No.: 11113-81-8
• Molecular Weight: 329.812
• Exact weight: 249.96
• EU number: 234-845-3
• HS code: 2846901700
• PSA Features: 3

Physico-chemical characteristics

• Melting point: 2183 °C

What do these numbers mean?

The melting point of 2183 °C classifies the material as a refractory oxide. Practical consequence: sintering ceramics and introducing oxide into the glass charge require high temperatures, and the compound itself maintains phase stability under conditions where most functional additives are already destroyed. Oxides of rare earth elements do not dissolve in water and are transferred into solution only by the action of acids.

Hazard classification

• Hazard Statements: H315 - Causes skin irritation
• GHS Warning: H315 (16.67%) - Causes skin irritation (skin corrosion/irritation)
• Precautions: P261, P264, P271, P273, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P403+P233, P405, P501
• Aggregated GHS information provided by 14 companies through 4 notifications to the ECHA C&L registry; one notification may apply to several companies

The share of 16.67% shows that not all notifiers indicated the irritant effect: the variation is due to differences in the dispersion and purity of product lots. Work practice is based on a more strict version of the classification.

Completeness of source data

The product card does not contain the chemical formula, appearance, density, boiling point, solubility, toxicity indicators, transport markings, water hazard class, RTECS number and prescribed storage conditions. These items are not included in the description. Information is requested from the safety data sheet and certificate of analysis for a specific batch, which also indicates the actual oxygen stoichiometry of the oxide.

Storage and handling

The container is tightly closed, the room is dry and ventilated. Praseodymium oxides absorb moisture and carbon dioxide from the air, so open storage reduces the content of the main substance. A set of precautionary measures from the card sets the operating mode: do not inhale dust and do not allow it to enter the environment (P261, P271, P273), use gloves, safety glasses and protective clothing (P280), in case of contact with skin, wash with plenty of soap and water (P302+P352), in case of contact with eyes, rinse with water for several minutes and remove contact lenses (P305+P351+P338), store in a well-ventilated place in a closed container (P403+P233) and dispose of the contents and container according to established rules (P501).