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Buffers are important to biological organisms because?

A radioactive nucleus Pb-208 undergoes an alpha decay. (a) write the complete nuclear reaction (b) if 420g of Pb-208 is initially present, how much will be left after 3 half-lives? (c) what is the mass percentage remaining after the 3 half-lives? Show work for full credit.

Based on the specific heats, which substance would take the most amount of energy to raise its temperature by one degree for every gram of that substance?

A gas at a temperature of 298 K has a pressure of 0.987 atm.  What will the pressure be at a temperature of 325 K, assuming no change in volume? (Show details of work for full credit, including writing the formula needed, defining your parameters, and solving for the unknown)

Rate of a reaction is dependent on all the following except?

Given the equation:  2 C2H2(g) + 3 O2(g)→ 4 CO2(g)+ 2 H2O(g), how many moles of oxygen gas are required to produce 8.0 moles of carbon dioxide?

The following reaction is an example of what type of chemical reaction? 2 Al + 3 CuSO4→ Al2(SO4)3 + 3 Cu

You will be required to scan/take a picture and upload to the Exam drop box folder as .PDF, .JPEG or .TIFF, any scrap paper and periodic table used, not more than 10 minutes after completing the Exam. Failure to do so will result in zero points for the Exam.

Which of the following is a basic pH value?

Define the following: (a)Radioactivity, (b) Saturated Solution (c) A buffer