Homework 7/17

Page 204 #1-6

1. An allotrope is a different form of an element that has different chemical and physical properties.

2. Oxygen and Silicon are all allotropes.

3. A) A diamond is the hardest rock known to man therefore it is denser and harder than a pencil and a chunk of coal. Pencil lead is made of graphite, and it is cheap, soft, and easy to find. A chunk of coal is also generic for barbequing and it is cheap. Diamonds are rare, expensive and expensive.

B) They all have different densities, costs, and atomic numbers and masses.

C) The atomic makeup of each of these elements affects their properties that make them so expensive or cheap.

4. Engineered products usually have more controlled and exact properties than natural products, because natural products are not man made. The natural products come as they are and indifferent.

5. 2 advantages: durable and have high melting points

2 disadvantages: brittle and crack easily

6. Plastic products can be made hard or soft based on what it is going to be used for. Two examples or soft plastic are water bottles and plastic bags. An example of hard plastic is glass and these products are hard or soft because different properties call for different uses.