If 80mg of a radioactive element decays to 10 mg in 30 mins., what is the element's half-life in minutes? a- 10  b- 20  c- 30  d- 40

the answer is a.10

Explanation:

in(No/N) = kt

No = 80 mg

N = 10 mg

t = 30 min

solve for k, then

k = 0.693/t1/2

Substitute k from above and solve for t1/2

10 min is correct.

the correct name for the n3 ion is azide. azide is a polyatomic anion with a -1 charge and is written as n3 -1. it consists of three nitrogen atoms bonded together. hope i . let me know if you need anything else.

- "the choice that is not an indicator of a chemical change is "state of matter changes". more common than not, chemical reactions produce energy in the form of light or heat. along with energy, they also produce a new substance called the product that could be in any state of matter (solid, gas, or liquid)."