How many helium atoms are in a helium blimp containing 495 kg of helium?

Principles of General Chemistry 2
How many total moles of ions are released when each of the following samples dissolves completely in water? (a) 0.734 mol of \(\mathrm{Na}_{2} \mathrm{HPO}_{4}\) (b) 3.86 g of \(\mathrm{CuSO}_{4} \cdot 5 \mathrm{H}_{2} \mathrm{O}\) (c) \(8.66 \times 10^{20}\) formula units of \(\mathrm{NiCl}_{2}\)

Statistics: Informed Decisions Using Data 4
Problem 17E In Problems (a) draw a scatter diagram of the data, (b) by hand, compute the correlation coefficient, and (c) determine whether there is a linear relation between x and y. x 2 4 6 6 7 y 4 8 10 13 20

Physics: Principles with Applications 7
(III) An atomic nucleus of mass m traveling with speed v collides elastically with a target particle of mass 2m (initially at rest) and is scattered at \(90^{\circ}\). (a) At what angle does the target particle move after the collision? (b) What are the final speeds of the two particles? (c) What fra

Chemistry 11
Acetaminophen is the active ingredient in Tylenol. (a) Write the molecular formula of the compound. (b) What is the hybridization state of each C, N, and O atom? (c) Describe the geometry about each C, N, and O atom.

OpenIntro Statistics 3
Buteyko method, study components. The Buteyko method is a shallow breathing technique developed by Konstantin Buteyko, a Russian doctor, in 1952. Anecdotal evidence suggests that the Buteyko method can reduce asthma symptoms and improve quality of life. In a scientific study to determine the eectiven

Chemistry: A Molecular Approach 3
Why is vaporization endothermic? Why is condensation exothermic?

Public Finance: A Contemporary Application of Theory to Policy 11
What are externalities? Use a supply-and-demand analysis to show how a negative or positive externality prevents a perfectly competitive market from achieving efficiency.

Biology: The Dynamic Science 5
What additional biological questions can be answered if one has the complete sequence of an organism's genome as compared with the sequences of individual genes?