4 A metal X was found to displace zinc from zinc nitrate solution but no displacement occurred when it was added to magnesium nitrate solution. Arrange the three metals, X, zinc and magnesium in decreasing order of ease of ionisation.

Dying the folding patterns of protein molecules can microbiologists better understand cellular processes as well as some diseases, such as alzheimer’s, that are caused by proteins that have misfolded. the folding of these complicated molecules can be simulated on computers, but it takes a lot of processor power and time for even expensive supercomputers to do this. a group of researchers at stanford university developed software that can be used to distribute the processing of data to anyone who is willing to donate time on their idle personal computers. as a result, the researchers have been able to achieve protein-folding simulations that are far better than those other computing methods have done. which statement best describes the work of these researchers? the work is not scientific because the data are not processed in one location. the work is not scientific because the simulations are not reproducible. the researchers applied creativity to solve a problem in running an experiment. the researchers used only well-established scientific techniques.

24. a sports ball is inflated to an internal pressure of 1.85 atm at room temperature (25 °c). if the ball is then played with outside where the temperature is 7.5 °c, what will be the new pressure of the ball? assume the ball does not change in volume nor does any air leak from the ball a) 0.555 atm b) 1.74 atm c) 1.85 atm d) 1.97 atm

Which statement correctly describes metallic bonds? a. they form when certain atoms lose electrons and other atoms gain electrons. b. they involve an attraction between anions and cations. they always involvpoth a metal and a nonmetal. d. they can only form between atoms of the same element. e. they form because electrons can move freely between atoms.