Q1: Blast furnace slag is mainly molten

ANS:A - sand

Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. Here's an explanation of sand:

1. Composition: Sand is primarily composed of small particles of minerals or rock fragments. The most common mineral found in sand is quartz (silicon dioxide, SiO2), but sand can also contain other minerals such as feldspar, mica, magnetite, and calcite. The composition of sand varies depending on its source and geological history.
2. Grain Size: Sand particles range in size from 0.0625 mm (fine sand) to 2 mm (coarse sand) in diameter, according to the Wentworth scale. The size of sand grains is often used to classify sand into different categories, such as fine sand, medium sand, and coarse sand.
3. Formation: Sand is formed through the weathering and erosion of rocks. Over time, rocks are broken down into smaller particles by physical processes such as abrasion, frost action, and chemical processes such as dissolution and hydrolysis. These processes gradually produce sand-sized particles that accumulate in various environments, such as riverbeds, beaches, deserts, and sand dunes.
4. Uses:
   • Construction: Sand is a key ingredient in construction materials such as concrete, mortar, and asphalt. It is used as a fine aggregate to bind together larger particles in these materials.
   • Landscaping: Sand is commonly used in landscaping for purposes such as filling gaps between pavers, creating beach-like features in gardens, and leveling uneven ground.
   • Industrial Applications: Sand is used in various industrial processes, including manufacturing glass, casting metal, and producing silicon chips for electronics.
   • Recreational Activities: Sand is a popular material for recreational activities such as building sandcastles, playing beach volleyball, and creating sand sculptures.
5. Environmental Importance: Sand plays a crucial role in ecosystem functioning and habitat formation. It provides habitat for various organisms, including burrowing animals and plants adapted to sandy soils. Sand dunes also act as natural barriers against coastal erosion and storm surges.

Overall, sand is a versatile and abundant natural resource with numerous uses in construction, industry, recreation, and environmental protection. Its availability and properties make it a valuable material in various human activities and natural processes.