- Iron sulfide can be formed by heating a mixture of powdered iron and sulfur
- Iron sulfide is made of iron and sulfur
- So, iron sulfide is made of a mixture of iron and sulfur being heated

- Iron is a kind of element
- Sulfur is a kind of element
- So, iron and sulfur are two elements

- Iron sulfide is made of a mixture of iron and sulfur being heated
- Iron and sulfur are two elements
- So, iron sulfide is made of two elements

- Iron sulfide is made of two elements
- A compound is made of two or more elements chemically combined
- Therefore, iron sulfide is a compound

Therefore, iron sulfide is a compound
Question
A mixture of powdered iron and sulfur is heated. What will be formed?

Context
- A compound is made of two or more elements chemically combined 
- Iron is a kind of element 
- Sulfur is a kind of element 
- Iron sulfide can be formed by heating a mixture of powdered iron and sulfur 
- Iron sulfide is made of iron and sulfur