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Calculate the atomic mass of element “X”, if it has 2 naturally occurring isotopes with the following masses and natural abundances: X-44           43.8776 amu         29.88% X-46           45.9443 amu         70.12% Final Exam Reference Sheet and Periodic Table

10 g of methane (CH4) is combusted with 5.0 g of oxygen to produce carbon dioxide and water according to the chemical equation shown below.  What is the limiting reactant (LR) and theoretical yield of CO2 in moles?                                     CH4 (g) + 2 O2 (g)  →  2 H2O (g) + CO2 (g) Final Exam Reference Sheet and Periodic Table

Use the data given below from a Born-Haber cycle to determine the electron affinity of Br.                                                                     H°(kJ)             K (s) →  K (g)                                      89             K (g) →  K⁺ (g) + e⁻                           419             ½ Br2 (l) →   Br (g)                             96             K (s) +  Br2 (g) →  KBr (s)                 -394             K⁺ (g) + Br⁻ (g) →  KBr (s)                 -674 Final Exam Reference Sheet and Periodic Table

An ecological footprint measures the amount of

An ecological footprint measures the amount of

There is a population increase in all of the following situations except

Both vitamin D and folate levels are affected by UV radiation from sunlight. Which correctly explains the effects of sunlight on these vitamins?

 In general, exponential population growth starts slowly and rapidly increases until

 In general, exponential population growth starts slowly and rapidly increases until

To determine the impact human populations have on an environment, scientists use which measurement?