F in Exams The Very Best Totally Wrong (2 page)

In a blast furnace it is impossible for aluminum to be extracted from its ores. Why?

What type of attractive force or bond holds the sodium ions and chloride ions together in a crystal of sodium chloride?

Over the last 50 years there has been a significant change in the concentration of carbon dioxide. Give a reason for this.

What are the characteristics of crude oil?

Describe the chemical differences between H
₂
O and CO
₂
.

What is a vibration?

What is the difference between a hydrocarbon (such as ethane) and an alcohol (such as ethanol)?

The burning of fossil fuels that contain carbon produces a gas called carbon dioxide. Draw a “dot-and-cross” diagram to represent carbon dioxide.

What is the lowest-frequency noise that a human can register?

What is the highest-frequency noise that a human can register?