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.

Identify which of the following are elements,mixtures,or compounds:
$(i)$ Brass $(ii)$ Diamond $(iii)$ Sand.

Classify the following into elements,compounds,and mixtures:
$(a)$ Sodium $(b)$ Soil $(c)$ Sugar solution $(d)$ Silver $(e)$ Calcium carbonate $(f)$ Tin
$(g)$ Silicon $(h)$ Coal $(i)$ Air $(j)$ Soap $(k)$ Methane $(l)$ Carbon dioxide $(m)$ Blood

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.

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

$(a)$ Define an element.
$(b)$ Identify non-metals from the following elements: Carbon,Potassium,Silicon,Chlorine,Mercury.