If a sample of a certain solution is determined to have a [h3o+][h3o+] concentration of 4.91×10−44.91×10−4 moles/liter, what is its ph? round off your answer to one decimal place.

One similarity and one difference between an element and a mixture of elements

8. what happens to matter during a chemical reaction

Which of these statements best explains why space exploration should be encouraged? it prepares humans to live without oxygen. it dispel myths about objects in space. it prevents comets and asteroids from striking earth. it creates technology to absorb harmful radiations in space.