State whether the following statement is true or false:
Metals are malleable,ductile,sonorous,and lustrous.

On heating,calcium carbonate gets converted into calcium oxide and carbon dioxide.
$(a)$ Is this a physical or a chemical change?
$(b)$ Can you prepare one acidic and one basic solution by using the products formed in the above process? If so,write the chemical equations involved.

State whether the following statement is true or false:
During the burning of a candle,only a chemical change takes place.

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.

How is heating of sugar and heating of ammonium chloride different from each other? Explain your answer.

Sucrose (sugar) crystals obtained from sugarcane and beetroot are mixed together. Will it be a pure substance or a mixture? Give reasons for the same.