What are metalloids? Give examples.

What is meant by a pure substance?

Elements are classified as metals,non-metals,and metalloids. Give any one property of each. Also,give one example of each.

When a bar magnet is brought closer to a mixture of iron filings and sulphur powder,iron particles stick to the magnet,whereas in the case of iron sulphide,no change is observed. When a mixture of iron and sulphur is added to carbon disulphide,sulphur dissolves,whereas in the case of iron sulphide,no change is observed. Justify the statement that the properties of a compound are different from its constituents,while a mixture shows the properties of its constituent elements using the example of iron and sulphur.

Differentiate between an element and a compound. Categorize the following substances into elements and compounds: Sodium chloride,Iodine,Water,$24$ carat gold,Oxygen gas,Carbon.

Differentiate between an element and a compound (any two points). Give one example each.