A neutral atom of barium lost two electrons, how many electrons would be left?

What is the percentage by mass of silicon (si) in iron aluminum silicate (fe3al2(sio4)3)?

There is an area in idaho named craters of the moon where most of the ground is covered with basalt, adark gray, igneous rock with no visibl crystals. what can you infer about the geographical history of the area?

Which of the following pressures is equal to 760 mm hg? 2.0 atm 101.3 pa 101,300 kpa 101,300 pa