What is the average atomic mass for element X if the percent abundances of its isotopes are: 5% for X-15, 11% for X16, and 84% for X18?

What is a main difference between a mixture and a pure substance? a mixture is only a liquid, but a pure substance can be in any state.a mixture looks the same throughout, but a pure substance does not.1 a mixture can vary in composition, but a pure substance has a set composlo a mixture can be made up of a single compound, but a pure substance car

How many moles of potassium are needed to react completely with 12.8 moles of magnessium bromide?

If a fast moving car making a loud noise approaches and moves past the person what will happen as the distance between the two increases?