Abstract: A chemical mechanical polishing aqueous dispersion including (A) silica particles, and (B1) an organic acid, the sodium content, the potassium content, and the ammonium ion content of the silica particles (A) determined by ICP atomic emission spectrometry, ICP mass spectrometry, or ammonium ion quantitative analysis using ion chromatography having a relationship in which the sodium content is 5 to 500 ppm and at least one of the potassium content and the ammonium ion content is 100 to 20,000 ppm.

Abstract: A deoxidizer includes a porous body of fluorite-type cerium oxide represented by CeOx (where x is a positive number smaller than 2) and having a reversible oxygen deficiency. The deoxidizer has a specific surface area of 0.6 to 1.8 m2/g and a pore median diameter of 1.6 to 5.3 ?m. The cerium oxide used for the deoxidizer is produced by: firing a cerium-containing salt in the atmosphere at 500° C. to 1400° C. for 1 to 20 hours, to produce fluorite-type cerium oxide composed of a porous body; and firing the cerium oxide at 700° C. to 1100° C. for 1 to 3 hours in a reducing atmosphere having a hydrogen concentration equal to or above the lower explosive limit, to remove oxygen from the cerium oxide and produce the fluorite-type cerium oxide represented by CeOx and having a reversible oxygen deficiency.

Abstract: A deoxidizer includes a porous body of fluorite-type cerium oxide represented by CeOx (where x is a positive number smaller than 2) and having a reversible oxygen deficiency. The deoxidizer has a specific surface area of 0.6 to 1.8 m2/g and a pore median diameter of 1.6 to 5.3 ?m. The cerium oxide used for the deoxidizer is produced by: firing a cerium-containing salt in the atmosphere at 500° C. to 1400° C. for 1 to 20 hours, to produce fluorite-type cerium oxide composed of a porous body; and firing the cerium oxide at 700° C. to 1100° C. for 1 to 3 hours in a reducing atmosphere having a hydrogen concentration equal to or above the lower explosive limit, to remove oxygen from the cerium oxide and produce the fluorite-type cerium oxide represented by CeOx and having a reversible oxygen deficiency.

Abstract: A chemical mechanical polishing aqueous dispersion includes (A) silica particles, and (B1) an organic acid, the number of silanol groups included in the silica particles (A) calculated from a signal area of a 29Si-NMR spectrum being 2.0 to 3.0×1021/g.

Abstract: A chemical mechanical polishing aqueous dispersion including (A) silica particles, and (B1) an organic acid, the sodium content, the potassium content, and the ammonium ion content of the silica particles (A) determined by ICP atomic emission spectrometry, ICP mass spectrometry, or ammonium ion quantitative analysis using ion chromatography having a relationship in which the sodium content is 5 to 500 ppm and at least one of the potassium content and the ammonium ion content is 100 to 20,000 ppm.