A sample of a radioactive isotope initially contains 20 x 10^10 atoms. After 16 days, 5 x 10^10 atoms remain. what is the half-life of the isotope?

A) 12 days

B) 20 days

C) 10 days

D) 16 days

E) 8 days

What is the 25 element in chemistry

Suggest why do you think people believe some theories even if they are not supported by credible evidence?

So for my science project it wants me to list the name of source. what is the [name of source]

If the initial volume of a graduated cylinder is 46mL and the final volume after an object is placed in it is 54mL what is the volume of the object?

What is the hardest mineral listed here? A. quartz B. calcite C. gypsum D. corundum

Lead oxide is formed when a lead cation that has a charge of 2 + combines with an oxygen anion that has a charge of 2-. Using the crisscross method, write the formula for lead oxide.

Why is it important to reduce coefficients in a balanced equation to the lowest possible whole-number ratio?

Which agent causes sand dunes to form? Ocean waves Gravity The wind carries the sand until it runs into an obstacle Weathering of old rocks in the desert

What does composition mean in science

Which of the following descriptions best describes a solid substance? A. The volume of the substance depends on the container it is in. B. Volume of the substance changes depending on its location. C. The shape of the substance changes often. D.