Exam 21: Metals and Solid-State Materials

-Which picture represents a p-type Si semiconductor?

A particular superconductor has eight copper atoms on corners and eight copper atoms on edges of its unit cell.How many copper atoms are attributed to a single unit cell of this superconductor?

Which one of the following is a metallic conductor at room temperature but a superconductor at 18 K?

What are the most abundant mineral in the earth's crust?

A diode has a negative bias when the p-type semiconductor is attached to the ________ (negative,positive)battery terminal,which ________ (inhibits,permits)electron flow.

Because nanoparticles have a larger percentage of atoms on the surface of the nanoparticle than on the surface of bulk material,nanoparticles have ________ melting points and ________ chemical reactivity than the bulk material.

Which metal has maximum filling of bonding molecular orbitals and minimal filling of antibonding molecular orbitals in its composite s-d band?

A light emitting diode with a band gap of 181 kJ/mol emits light in what region of the electromagnetic radiation spectrum?

Which of the following elements is most likely to occur as a metal sulfide ore?

Which one of the following is an electrical insulator?

Who discovered the phenomenon of superconductivity in 1911?

Which substance is the best conductor of electricity?

The wavelength of light emitted by the GaP_0.40As_0.60 LED,which has a band gap of 181 kJ/mol,is ________ nm.

The following picture shows the electron populations of the bands of MO energy levels for elementary silicon. -In this picture the conduction band is given by letter(s)

Look at the location of elements A,B,C,and D in the following periodic table. -Which of these elements is likely to be found in nature as a carbonate?

One source of titanium is pyrophanite,MnTiO₃.The oxidation states of manganese and titanium in pyrophanite are ________ and ________,respectively.

Which of the following metals is commonly obtained by electrolysis?

What is not an appropriate method of isolating the metals shown?

Which element is likely to be a principal impurity in zinc ore?

The following pictures show the electron populations of the composite s-d bands for four different transition metals. -Which metal has the lowest melting point?