Materials containing the elements Y, Ba, Cu, and O that are superconductors (electrical resistance equals zero) at temperatures above that of liquid nitrogen were recently discovered. The structures of these materials are based on the perovskite structure. Were they to have the ideal perovskite structure, the superconductor would have the structure shown in pant (a) of the following figure. a. What is the formula of this ideal perovskite material? b. How is this structure related to the perovskite structure shown in Exercise 85? These materials, however, do not act as superconductors unless they are deficient in oxygen. The structure of the actual superconducting phase appears to be that shown in pan (b) of the figure. c. What is the formula of this material?
Materials containing the elements Y, Ba, Cu, and O that are superconductors (electrical resistance equals zero) at temperatures above that of liquid nitrogen were recently discovered. The structures of these materials are based on the perovskite structure. Were they to have the ideal perovskite structure, the superconductor would have the structure shown in pant (a) of the following figure. a. What is the formula of this ideal perovskite material? b. How is this structure related to the perovskite structure shown in Exercise 85? These materials, however, do not act as superconductors unless they are deficient in oxygen. The structure of the actual superconducting phase appears to be that shown in pan (b) of the figure. c. What is the formula of this material?
Solution Summary: The author explains how the formula of given superconductor and ideal perovskite is determined, and the two major types of close packing of the atoms/ions in a crystal structure are – hexagonal close
Materials containing the elements Y, Ba, Cu, and O that are superconductors (electrical resistance equals zero) at temperatures above that of liquid nitrogen were recently discovered. The structures of these materials are based on the perovskite structure. Were they to have the ideal perovskite structure, the superconductor would have the structure shown in pant (a) of the following figure.
a. What is the formula of this ideal perovskite material?
b. How is this structure related to the perovskite structure shown in Exercise 85?
These materials, however, do not act as superconductors unless they are deficient in oxygen. The structure of the actual superconducting phase appears to be that shown in pan (b) of the figure.
2. Platinum and other group 10 metals often act as solid phase hydrogenation catalysts for
unsaturated hydrocarbons such as propylene, CH3CHCH2. In order for the reaction to be
catalyzed the propylene molecules must first adsorb onto the surface. In order to completely
cover the surface of a piece of platinum that has an area of 1.50 cm² with propylene, a total
of 3.45 x 10¹7 molecules are needed. Determine the mass of the propylene molecules that
have been absorbed onto the platinum surface.
Chem 141, Dr. Haefner
2. (a) Many main group oxides form acidic solutions when added to water. For example solid
tetraphosphorous decaoxide reacts with water to produce phosphoric acid. Write a balanced
chemical equation for this reaction.
(b) Calcium phosphate reacts with silicon dioxide and carbon graphite at elevated temperatures
to produce white phosphorous (P4) as a gas along with calcium silicate (Silcate ion is SiO3²-)
and carbon monoxide. Write a balanced chemical equation for this reaction.
Problem Set 4a Chem 1411. A latex balloon is filled with a total of carbon dioxide gas so that its volume reaches 1.352 L. The balloon whose weight was originally 0.753 g, now weighs 2.538 g. How many molecules of carbon dioxide have been added to the balloon?
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Unit Cell Chemistry Simple Cubic, Body Centered Cubic, Face Centered Cubic Crystal Lattice Structu; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=HCWwRh5CXYU;License: Standard YouTube License, CC-BY