Please help! Check the element pairings that are likely to react with each other. Refer to the periodic table for assistance

1. Li and Be
2. Rb and Br
3. Fr and Cl
4. Rb and Ca
5. Li and Cl
6. F and Ne

Fossil fuels are organic compounds that are made from

Rank the four gases (air, exhaled air, gas produced from from decomposition of h2o2, gas from decomposition of nahco3) in order of increasing concentration of co2

Which of the following statements is true about energy quantization at the atomic level? electrons in the outermost orbits are the most stable. electrons in all the orbits around the nucleus have the same amount of energy. electrons in the orbit closest to the nucleus have the least amount of energy. electrons absorb or release the same amount of energy independent of the energy levels.