Rezolvati urmatoarele probleme, urgent, dau coroana 1. În 400 grame soluţie se găsesc 80 grame zahăr. Ce concentraţie procentuală are soluţia?
2. În 500 Kg soluţie sunt dizolvate 75 Kg sodă de rufe. Ce concentraţie procentuală are soluţia ?
3. Ce cantitate de soluţie de concentraţie 15% se obţine prin dizolvarea a 60 Kg piatră vânătă în apă ?

When a comet collides with earth, it adds material to our planet and causes great damage. therefore, a collision like this is a a. destructive force b. constructive force c. geologic process and event d. constructive and destructive force

In an investigation that uses the scientific method, which step immediately follows making a hypothesis? o summarizing the results o asking a question o making observations designing an experiment mark this and retum save and exit next submit

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