State the term- solubility

Solid solutions are made of a host, the solvent or matrix) which dissolves the solute (minor component). The ability to dissolve is known as solubility. Solid solutions are: 

• Homogeneous
• Maintain crystal structure
• Contain randomly dispersed impurities (substitutional or interstitial)

Factors for high solubility 

• Same atomic size (to within 15%)
• Same crystal structure
• Same electro negativity (otherwise a compound is formed)
• Same valence