Question

1.

A rare metal alloy is a superconductor at -250 ^oC . What is the temperature on the Kelvin scale?

Group of answer choices

a. -523 K

b. -250 K

c. -23 K

d. 23 K

e. 523 K

2. The radioactive disintegration of an atom of  146C yields 147 N and ?

Group of answer choices

a. alpha particle

b. beta particle

c. neutron

d. positron

3. A particular radioactive element has a half - life of 30.0 days. What percent of the original sample is left after 90.0 days?

Group of answer choices

a. 25

b. 50

c. 12.5

d. 6.25

Answer 1