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Bohr was the first to use the term “orbit” to explain the fixed energy levels of electrons.

How many years will it take $2 million to grow to $6.00 million with an annual interest rate of 9 percent? (Do not round intermediate calculations)

What annual rate of return is earned on a $1,000 investment when it grows to $2,300 in six years? (Do not round intermediate calculations. Round your answer to 2 decimal places.)

Kirkium is a made up metal element with a chemical symbol Km. The atomic mass of Km is 234.5 g/mol. The salt kirkium (I) carbonate, Km2CO3 is a slightly soluble salt that has a solubility product constant = 5.2×10-18.  You must show work in your upload for full credit, including the chemical equation. Enter your answers in E format, no spaces. Use correct sig figs! NO units here but show correct units in your upload.  A) Calculate the molar solubility of kirkium (I) carbonate in a saturated solution in pure water. [s1] M B) Calculate the molar solubility of kirkium (I) carbonate in a solution of 0.030 M Km2SO4 (Km2SO4 is a soluble salt.) [s2] M

Europium (Eu) is a lanthanide element.

Two moths with similar markings each produce a chemical that makes their bird predators sick to their stomach if eaten. Which principle of ecology does this dmeonstrate?

Explain the difference between primary and secondary successions and give an example of each.

Wingardic acid is a madeup monoprotic acid that has a Ka of 1.9×10-7. Consider the titration of 48.00 mL of 0.350 M wingardic acid with 0.420 M NaOH. Note that the concentrations are not the same. Make sure sig figs are correct on your answers. Don’t round until the end. Show your work on your upload for full credit. As usual, work should follow examples as in lecture, showing BRA and/or ICE tables if appropriate and any assumptions you are making. You can use a generic HA for the acid formula. A.  The half equivalence point will be at ______ mL of titrant added and have a pH of ______? vol titrant = [v1] mL pH = [ph1] B. The equivalence point will be at ______ mL of titrant added and have a pH of ______? vol titrant = [v2] mL pH = [ph2] C.  What is the pH at the point when 44.5 mL of titrant are added? pH = [ph3]               

A 6.80 percent coupon bond with 14 years left to maturity is priced to offer a yield to maturity of 7.5 percent. You believe that in one year, the yield to maturity will be 7.1 percent. What is the change in price the bond will experience in dollars? (Do not round intermediate calculations. Round your final answer to 2 decimal places.)

 As a general rule, for each jump up in trophic level, about how much does the available energy drop?