Relative abundance and atomic mass of the naturally occurring isotopes of hafnium: 5 % - 176 amu
19% -177 amu
27% 178 amu
14% - 179 amu
35% -180 amu
What is the average atomic mass of hafnium?
A)
176 amu
B)
177 amu
179 amu
D)
180 amu

Agas in a balloon at constant pressure has a volume of 160 ml at -125*c. what is its volume at 29.0*c?

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.

Avariable that is not being directly tested during an experiment should be changed varied experimented controlled