Describe in your own words why lithium, magnesium, and boron (groups 1,2,13) elements tend to form positive ions and fluorine, oxygen, and nitrogen (groups 15,16,17) tend to form positive ions.

An element has three stable isotopes with masses of 27.977 amu, 28.976 amu, and 29.973 amu. The heavier two isotopes have an abundance of 4.68% and 3.09%, respectively. What is the mass of the element? A) 29.251 B) 27.684 C) 28.085 D) 28.991 E) 30.

True of False: Only conclusions that support the hypothesis should be reported in scientific research.

A sample of CO2 gas has a volume of 12.0 L at STP. Calculate the number of moles of CO2 in the sample.

Which of these is an example of a chemical change? A. breaking glass B. melting ice on the windshield C. burning gasoline D. denting a bumper

Which economic goal does a society consider when deciding the best way to distribute its wealth?

How many millimeters are equal to 0.399195L

If heat energy is absorbed by the system during a chemical reaction, the reaction is said to be

A chemist has evolved a certain substance in water the chemist knows that more the substance could be dissolved into the water before it stops dissolving therefore the current solution is

Be sure to answer all parts. The combustion of a 40.0-g gaseous mixture of H2 and CH4 releases 3766 kJ of heat. Calculate the amount of each gas in grams.

Global warming can be slowed or stopped