Chemistry in Context UPDATED Test Questions And CORRECT Answers

How much carbon is in coal? 85% What is the chemical formula for coal? C135H96O9NS What is in coal? Carbon, hydrogen, oxygen, nitrogen, sulfur What do the components of coal come from? The smaller amounts of hydrogen, oxygen, nitrogen, and sulfur come from the ancient plant material and other substances present when the plants were buried What types of grades of coal are there? Coal occurs in varying grades, but all grades are better fuels than wood because they contain a higher percentage of carbon and a lower percentage of oxygen What is the relationship between oxygen and energy? Generally speaking, the more oxygen a fuel contains, the less energy per gram it releases on combustion. In other words, oxygen-containing fuels lie lower on the potential energy scale