Which of the following describes a homogeneous mixture? (2 points) question 18 options: 1) it can be separated by chemical means but not by physical means. 2) it cannot be separated by either chemical or physical means. 3) it can be separated by physical means and is uniform in composition. 4) it can be separated by physical means and is not uniform in composition.

How do the energy differences between the higher energy levels of an atom compare with the energy difference between the lower energy level of the atom

Calculate the ratio of h+ ions to oh– ions at a ph = 7. find the concentration of h+ ions to oh– ions listed in table b of your student guide. then divide the h+ concentration by the oh– concentration. record this calculated ratio in table a of your student guide. compare your approximated and calculated ratios of h+ ions to oh– ions at a ph = 7. are they the same? why or why not? record your comparison in table a. what is the concentration of h+ ions at a ph = 7? mol/l what is the concentration of oh– ions at a ph = 7? mol/l what is the ratio of h+ ions to oh– ions at a ph = 7? : 1

What does a complete balanced chemical equation include? a. exothermic coefficients b. endothermic coefficients c. valence electrons d. molar coefficients