The unit “troy ounce” is often used for precious metals such as gold (Au) and platinum (Pt). (1 troy ounce = 31.103 g.) (a) A gold coin weighs 2.41 troy ounces. Calculate its mass in grams. (b) Is a troy ounce heavier or lighter than an ounce? (1 lb =16 oz; 1 lb = 453.6 g.)

Introductory Chemistry 5
How many joules of nutritional energy are in a bag of chips with a label that lists 245 Cal? If 1 lb of fat is stored by the body for each \(14.6\times10^3\mathrm{\ kJ}\) of excess nutritional energy consumed, how many bags of chips contain enough nutritional energy to result in 1 lb of body fat?

Introductory Chemistry 5
What are the basic unitssingle atoms, molecules, or formula unitsthat compose each substance? (a) \(\mathrm{Rb}_{2} \mathrm{O}\) (b) \(\mathrm{N}_{2}\) (c) \(\mathrm{Fe}\left(\mathrm{NO}_{3}\right)_{2}\) (d) \(\mathrm{~N}_{2} \mathrm{~F}_{4}\)

Biology 8
Some bacteria are metabolically active in hot springs because a. they are able to maintain a lower internal temperature. b. high temperatures make catalysis unnecessary. c. their enzymes have high optimal temperatures. d. their enzymes are completely insensitive to temperature. e. they use molecules

Campbell Biology in Focus - Standalone book 1
A typical prokaryotic cell has about 3,000 genes in its DNA, while a human cell has about 20,500 genes. About 1,000 of these genes are present in both types of cells. Based on your understanding of evolution, explain how such different organisms could have this same subset of genes. What sorts of fun

Macroeconomics 22nd
Why is a quota more detrimental to an economy than a tariff that results in the same level of imports as the quota? What is the net outcome of either tariffs or quotas for the world economy?

Biology 2e by Openstax
Potassium has an atomic number of 19. What is its electron configuration? a. shells 1 and 2 are full, and shell 3 has nine electrons b. shells 1, 2 and 3 are full and shell 4 has three electrons c. shells 1, 2 and 3 are full and shell 4 has one electron d. shells 1, 2 and 3 are full and no other elec

Urban Economics 8
Education Spillover Benefi ts Consider a city where the initial wage of high-school dropouts is $10. Suppose the college share of the workforce increases by 2 percent. Use a demand-supply graph of the labor market for high-school dropouts to show the effects on the dropout wage. Use the numbers provi

Chemistry 13
Define the following terms: electromotive force and standard reduction potential.