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This energy diagram shows the allowed energy levels of an electron in an atom: Which transition causes the emission line at the shortest wavelength?

By 1000 Vikings were mostly no longer considered a threat as a result of the feudal system, better climate in Denmark, and conversion to Christianity. Thus their conquest of Western Europe ended.

A chemical reaction takes place inside a flask submerged in a water bath. The water bath contains 7.40 g of water at 20.3 C. During the reaction, 145 J of heat flows out of the bath and into the flask. The heat capacity of water is 4.18 J/(gK). Calculate the new temperature of the water bath.  q=cmT. 

The major species of KOH present when dissolved in water are

The largest Christian Church, called the Hagia Sophia, was built in France by Charlemange in honor of being crowned the Holy Roman Emperor in 800 CE.

Calculate the density of carbon monoxide gas at exactly 250 K and 0.20 atm. You can assume carbon monoxide gas behaves as an ideal gas. Formula: PM=dRT. The molar mass of CO is 28.01 g/mol. R = 0.0821 atmL/(molL)

It takes 614 KJ/mol to break a carbon-carbon bond. Calculate the maximum wavelength of light for which a carbon-carbon bond could be broken by absorbing a single photon. Report the value in nanometer. Pay attention: the unit given is …/mol whereas the questions asks the breaking of ONE carbon-carbon bond. Energy per photon = hc/.           h=6.6261034 Js.       c=2.998108 m/s.        Avogadro constant = 6.0221023.

Which groups invaded into Western and Eastern Europe during the 8th, 9th, and 10th centuries CE. Select 3.

Clean agent fire suppression systems are best suited for:

After the Fall of Rome around 400 CE, the Franks moved into Gaul, making France the earliest centralized government by the late Medieval period.