A radioactive isotope has a half-life of 45 minutes. How long would it take for a sample of this isotope to decay to the point where only 10% of the original amount is still there

Asolution is prepared using 0.125 glucose c6h12o6 is enough water to make 250 g of total solution the concentration of the solution, expressed in parts per million is

How many grams of oxygen gas are contained in a 15 l sample at 1.02 atm and 28°c? show your work.

Problem page combustion of hydrocarbons such as pentane ( c5 h12 ) produces carbon dioxide, a "greenhouse gas." greenhouse gases in the earth's atmosphere can trap the sun's heat, raising the average temperature of the earth. for this reason there has been a great deal of international discussion about whether to regulate the production of carbon dioxide.(a) write a balanced chemical equation, including physical state symbols, for the combustion of liquid pentane into gaseous carbon dioxide and gaseous water. (b) suppose 0.350 kg of pentane are burned in air at a pressure of exactly 1 atm and a temperature of 20.0 degree c. calculate the volume of carbon dioxide gas that is produced. be sure your answer has the correct number of significant digits.