Cu + AgNO 3 = Cu(NO 3) 2 + Ag: single replacement: Cu + O 2 = CuO: synthesis: Cu + O 2 = Cu 2 O: synthesis: Cu + HCl = CuCl 2 + H 2: single replacement: Cu + Cl 2 = CuCl 2: synthesis. Copper, isotope of mass 65. Molecular Weight. 64.927789 g/mol. Cu atomic mass = Cu-63 mass. Cu-63 abundance + Cu-(Isotope) mass. Cu-(Isotope) abundance. Since there are two naturally occuring isotopes and we know that Cu-63 is one isotope that appears @ 69.17% abundance, the other isotope must appear @ % abundance. Once you calculate that, you can solve the equation given again below: Cu atomic mass. Seven metastable isotopes have been characterized; 68m Cu is the longest-lived with a half-life of 3.8 minutes. Isotopes with a mass number above 64 decay by β −, whereas those with a mass number below 64 decay by β +. 64 Cu, which has a half-life of 12.7 hours, decays both ways.
| Isotope | Atomic mass (Da) | Isotopic abundance (amount fraction) |
|---|---|---|
| 63Cu | 62.929 597(3) | 0.6915(15) |
| 65Cu | 64.927 790(5) | 0.3085(15) |
In 1961, the Commission recommended Ar(Cu) = 63.54 based on the recent chemical determinations. Divinity 2 well crafting. In 1967, the Commission recommended Ar(Cu) = 63.546(1) based on the mass-spectrometric measurements. The recommended uncertainty was increased to 0.003 in 1969 to include natural variations of up to approx. 0.15 % in the isotopic abundances of copperisotopes, and given the annotation 'r' to indicate that the precision was limitedby natural variability.
In the compilation by the Commission, the lowest reported δ65Cu value in a naturallyoccurring sample is −7.65 ‰ (x(65Cu) = 0.3066 and Ar(Cu) = 63.542) for a specimenof a Cu-chloride mineral (atacamite) from Chile. The highest reported δ65Cu is +9 ‰ (x(65Cu) = 0.3102 and Ar(Cu) = 63.549) for a Cu-carbonate mineral (aurichalcite) from Arizona. Some of these values are outside the range of the stated atomic-weight uncertainty andmay justify a re-evaluation by the Commission of the atomic-weight uncertainty or annotations
© IUPAC 2003
CIAAW
Mass Number Of Copper
Copper
Ar(Cu) = 63.546(3) since 1969
The name derives from the Latin cuprum for Cyprus, the island where the Romans first obtained copper.The symbol Cu also comes from the Latin cuprum. The element has been known since prehistoric times.
Where Does The Symbol Cu Come From
Isotopic reference materials of copper.