Tag: metals

Quizzes (9) Questions (306)

Questions Related to metals

Multiple choice chemistry metals physical properties of non-metals uses of metals and non metals physical properties of metals and non-metals

Which non-metal has semi-conductor property?

  1. Boron

  2. Carbon

  3. Silicon

  4. Magnesium
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Silicon is a tetravalent metalloid. Pure silicon is used to produce silicon wafers in the semiconductor industry. Pure silicon is an intrinsic semiconductor as it conducts electron holes and increases electrical conductivity. Silicon is doped with other microelements to increas its conductivity. It is used in transistors, solar cells, semiconductor devices.

Multiple choice chemistry metals physical properties of non-metals uses of metals and non metals physical properties of metals and non-metals

Why are non-metals poor conductors of electricity?

  1. They have high melting point

  2. They vibrate at high speed

  3. They do not have free electrons

  4. All of above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Non-metals are not dense enough and do not have enough free electrons to pass electricity efficiently. Electrons in non-metals are held tightly , they are no allowed to move freely .

Multiple choice chemistry metals physical properties of non-metals uses of metals and non metals physical properties of metals and non-metals

Why non-metals have a dull appearance?

  1. They have many free electrons

  2. They gain electrons easily

  3. They do not have lustre

  4. All of above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Non-metals vary greatly in appearance. They do not have lustre. As it does not have any free electrons light falling on non-metals does not reflect and hence non-metals are not shiny. Hence, they have a very dull appearance.

Multiple choice chemistry metals physical properties of non-metals uses of metals and non metals physical properties of metals and non-metals

Which of the following non-metal is hard yet brittle?

  1. Graphite

  2. Selenium

  3. Sulphur

  4. Diamond
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Diamond is the hardest substance known to man with a hardness of 10.0. It is brittle sometimes because it grows in diamond shape crystals, sometimes there are tiny cracks or flaws in the diamond and a hard strike against the crack of course will cause the diamond to crack into many pieces. Crystalline materials have planes of variable shear and normal strengths hence, they fail on fracture mechanism. Also, crystalline nature makes them extremely strong at surface resisting scratch.