Question

(a) Why is sodium electropositive in nature? What happens when sodium
is placed in a dish containing cold water? Explain with the help of
chemical equation.
(b) Why is 22 carat gold considered as an alloy?​

Answer 1

Answer:

b = The 22 Karat gold is mostly used in making jewellery. In 22K gold, 22 parts of the metal are gold and rest two comprises of metals like silver, zinc, nickel, and other alloys. It is also known as 91.67 per cent pure gold. Mixing alloys makes the texture of gold harder and hence jewellery becomes durable.

Explanation:

Answer 2

Explanation:

Because hydrogen is a nonmetal while sodium is a metal and tends to lose electrons because of metallic bonds present. That's why the electropositivity value of sodium is greater than hydrogen. The elements that can easily lose electrons to form positive ions are called electropositive elements, for example: metals.

if sodium is placed in cold waterMetals react with water and produce a metal oxide and hydrogen gas. ... Metals like potassium and sodium react violently with cold water. In case of sodium and potassium, the reaction is so violent and exothermic, that evolved hydrogen immediately catches fire."

b) The 22 Karat gold is mostly used in making jewellery. In 22K gold, 22 parts of the metal are gold and rest two comprises of metals like silver, zinc, nickel, and other alloys. It is also known as 91.67 per cent pure gold. Mixing alloys makes the texture of gold harder and hence jewellery becomes durable.