Nuclear Study Guide

An unstable nucleus .

• increases its nuclear mass through fission

• expels all of its neutrons

• increases its half-life

• emits energy when it decays

What does the 238 represent in plutonium-238?

• the mass number

• the atomic number

• the number of neutrons

• mass defect

What is the charge on a gamma ray?

• 0

• -1

• +1

• +2

What particle is emitted in an alpha decay?

• electron

• proton

• photon

• helium nucleus

A beta particle is a(an) .

• photon

• helium nucleus

• electron
• neutron

What is the least penetrating form of radiation?

• beta radiation

• alpha radiation

• gamma rays

What particle does argon-39 emit when it decays to potassium-39?

• neutron

• beta particle

• proton

• alpha particle

What element does polonium-208 decay to when it emits an alpha particle?

• 210 Pb 82

• 210 Po 82

• 204 Pb 82

• 214 Rn 86

The half-life for gold-198 is 2.69 days. An original sample of gold-198 has a mass of 10.0 g. How much of this sample will remain after 10.76 days?

• 0.625 g

• 2.50 g

• 40.0 g

• 160. g

0.313g of sodium-24 will remain after 90 hrs, if the initial sample was 20.0 grams. What is the half-life?

• 15 hrs

• 63.9 hrs

• 0.625 hrs

• 30 hrs