What are two key characteristics of a good scientific investigation

What does x represent in the formula for the compound xcl4?

When a spring is compressed, the energy changes from kinetic to potential. which best describes what is causing this change?

8) a mixture of he, ne and ar has a pressure of 7.85 atm. if the ne has a mole fraction of 0.47 and 8) ar has a mole fraction of 0.23, what is the pressure of he? a) 4.2 atm b) 3.7 atm c) 5.5 atm d) 2.4 atm e) 1.8 atm