Silicon doesn't contain other chemicals or substances in the same way that a mixture does. Silicon is an element, meaning it's a pure substance that cannot be broken down further by chemical means. However, silicon can form compounds with other elements. Here are four examples of compounds containing silicon:

1. Silicon Dioxide (SiO₂): This is the most common compound of silicon, found in sand, quartz, and glass.

2. Silicon Carbide (SiC): This is a very hard and abrasive material used in cutting tools, sandpaper, and ceramics.

3. Silicon Nitride (Si₃N₄): This is a strong, heat-resistant ceramic used in engine parts, bearings, and electronics.

4. Silicone Polymers: These are synthetic polymers containing silicon, oxygen, and carbon. They are flexible, water-resistant, and have diverse applications, from sealants and lubricants to medical implants.

These are just a few examples of the many compounds that silicon forms. Silicon's ability to bond with other elements gives it a wide range of applications in various industries.