Answer: Scientists have found interstellar hydrogen atoms

Introductory Chemistry 5
For each compound, list the correct formula and calculate the formula mass. (a) tin(IV) sulfate (b) nitrous acid (c) sodium bicarbonate (d) phosphorus pentafluoride

College Physics 1
Problem 20PE At takeoff, a commercial jet has a 60.0 m/s speed. Its tires have a diameter of 0.850 m. (a) At how many rev/min are the tires rotating? (b) What is the centripetal acceleration at the edge of the tire? (c) With what force must a determined 1.0010?15 kg bacterium cling to the rim? (d)

Organic Chemistry 7
Which is a stronger base? a. \(H S^{-} \text {or } H O^{-}\) c. \(\mathrm{CH}_{3} \mathrm{OH} \text { or } \mathrm{CH}_{3} \mathrm{O}^{-}\) e. \(\mathrm{CH}_{3} \mathrm{COO}^{-} \text {or } \mathrm{CF}_{3} \mathrm{COO}^{-}\) b. \(\mathrm{CH}_{3} \mathrm{O}^{-} \text {o

Krugman's Economics for AP® (High School) 2
Explain whether each of the following events represents (i) a change in supply or (ii) a movement along the supply curve. a. During a real estate boom that causes house prices to rise, more homeowners put their houses up for sale. b. Many strawberry farmers open temporary roadside stands during harve

Human Physiology: From Cells to Systems 9
Define tropic hormone.

General Chemistry. Principles and Modern Applications 11
When an iron object rusts, its mass increases. When a match burns, its mass decreases. Do these observations violate the law of conservation of mass? Explain.

Biology: The Dynamic Science 5
How do the concepts of gradualism and uniformitarianism in geology undermine the belief that earth is only about 6,000 years old?

Biology for AP Courses
How many different offspring genotypes are expected in a trihybrid cross between parents heterozygous for all three traits? How many phenotypes are expected if the traits behave in a dominant and recessive pattern? a. 64 genotypes; 16 phenotypes b. 16 genotypes; 64 phenotypes c. 8 genotypes; 27 pheno