Abstract: The possibility that nano-Cu dissolves in a dilute acid was analyzed theoritically，the thermodynamic relation between the solubility and the particle size of a nano-metal was derived. Besides，it was determined that the solubility of nano-Cu with different sizes in the dilute sulphuric acid，and the effect of particle size on the solubility was discussed. The results show that the particle size of nano-Cu has a considerable influence on the solubility in dilute sulphuric acid; the blocky Cu，which is insoluble in a dilute acid，can dissolve in a dilute acid when turned into nano-Cu with certain sizes，and the smaller the diameter，the higher the solubility，and the logarithm of the solubility has linear relation with the reciprocal of the diameter; and the experiment results are in accordance with the theoretic analysis.

Key words: nano-Cu, particle size, solubility, dilute sulphuric acid

摘要： 首先从理论上分析了纳米铜在稀酸中溶解的可能性，导出了溶解度与粒度间的热力学关系式；然后测定了不同粒径的纳米铜在稀硫酸中的溶解度，讨论了粒度对纳米铜在稀酸中溶解的影响规律。研究结果表明：粒度对铜在稀酸中的溶解度影响很大；不溶解于稀硫酸中的块状铜，制备成一定粒度的纳米铜后能够溶解于稀酸中，粒度越小溶解度越大；并且纳米铜溶解度的对数与其粒径的倒数呈线性关系；其实验结果与理论分析完全一致。

关键词: 纳米铜, 粒度, 溶解性, 稀硫酸