The core of the 40 calcium atom, the most common isotope is symbolized by ₂₀⁴⁰ca. 1) indicate the composition of the atom of calcium. 2) calculate its mass. compare it to the core's one. what can you say ? mass of a nucleon : mnucleon = 1,67 x 10⁻²⁷ kg. mass of an electron : melctron = 9,11 x 10⁻³¹ 3) there are three other stable isotopes of calcium. knowing that they possess respectively two, three and four neutrons more than the calcium 40, to give the symbol of their core. 4) wich ion does it form ?

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.

If you add 10ml of hot water to 10ml of cold water and the change in tempature 8°c calculate how much energy is gained by the cold water

What is the independent variable in this investigation? mass volume sample number substance density