Alloys Cmon

Which of the following statements explain why alloy is harder than its pure metal?

• Atoms in the alloy can vibrate

• Atoms in the alloy are difficult to slide

• Atoms in an alloy are arranged in an orderly manner

• More empty spaces between atoms in an alloy

What is / are the aims to make alloy?

• To increase strength and hardness of pure metals

• To improve appearance of metals

• To lower the melting point of pure metals

• To improve the resistance to corrosion of pure metals.

An alloy X has copper as main component and used for medal or monuments making. What is X?

• Bronze

• Brass

• Pewter

• Steel

The purity of gold alloy is measured using Karat (K) unit. 24 K gold is a gold without other mixture of metals. 18 K gold is a mixture of 18 parts of pure gold and 6 parts of other metals such as copper. What is the difference between 24 K gold and 18 K gold?

• 18 K gold can be easily bent compared to 24 K gold

• 18 K gold corrode easily compared to 24 K gold

• 24 K gold is harder than 18 K gold

• 24 K gold is softer than 18 K gold

Which of the following alloy is used to make the body or aeroplane?

• Duralumin

• Brass

• Stainless steel

• Pewter

Stainless steel is used to make the kitchen utensil. Which of the following element is added into iron to produce stainless steel?

• Chromium

• Copper

• Nickel

• Carbon

Which of the following statements is best explain why pure metals are malleable causing its shape can be easily changed?

• There are empty spaces between metal atoms. When force applied layers of atoms slide and fill the empty spaces

• The metal atoms arranged in orderly manner. When force applied atoms will vibrate and move faster.

• There are no empty spaces between metal atoms. When force applied layers of atoms slide and pure metal change shape

• There are empty spaces between metal atoms. When force applied layers of atoms slide and fill the empty spaces