QUESTION: Which of the following is not an element?
A Graphite
B Germanium
C Silica
D Silicon
ANSWER: Silica
| Element | Compound | ||
| Name of element | Uses | Name of compound | Uses |
| Hydrogen (H)
| · Hydrogen fuel cells · Chemical synthesis | Silica (SiO2) | · Glass manufacturing · Abrasives · Electronics |
| Oxygen (O)
| · Respiration · Combustion · Metal production | Water (H2O) | · Drinking · Hydration · Industrial processes |
| Carbon (C)
| · Organic compounds · Fuel · Building materials | Carbon Dioxide (CO2) | · Photosynthesis carbonation · Fire extinguishing |
| Silicon (Si)
| · Electronics · Semiconductors · Glass · Ceramics | Sodium Chloride (Nacl) | · Seasoning · Food preservation · Industrial processes |
| Iron (Fe)
| · Construction · Machinery · Steel production | Ethanol (C2H5OH) | · Alcohol for beverages · Fuel · Solvent |
| Copper (Cu)
| · Electrical wiring · Plumbing · Electronics | Methane (CH4) | · Natural gas · Fuel · Carbon source |
| Germanium (Ge) | · Semiconductors · Optics · Infrared devices | Hydrogen Peroxide (H2O2) | · Bleaching · Disinfection · Rocket propellant |
| Graphite (C) | · Lubricants · Pencils · Electrodes | Ammonia (NH3) | · Fertilizers · Cleaning products · Refrigeration |