How many electrons does carbon need to gain to obtain a noble gas electron configuration

How many atoms are there in 5.70 mol of mg

Estimate the molar mass of the gas that effuses at 1.6 times the effusion rate of carbon dioxide.

What effect would average population growth have on land usage? a. urban use of land would rise to more than 30 percent of available land. b. industrial use of land would rise to more than 30 percent of available land. c. the percentage of available land used as cropland would stay the same. d. cropland would fall to about 10 percent of available land.