Review radioactivity

From the nuclear belt of stability, you can see that

• As atoms increase in atomic number, more neutrons are needed to achieve a stable isotope

• As atoms increase in atomic number, fewer neutrons are needed to achieve a stable isotope

• As atoms decrease in atomic number, more neutrons are needed to achieve a stable isotope

• There is no relationship between the atomic number and the number of neutrons

Tags

NGSS.HS-PS1-8

Determine the number of protons and neutrons in a
 nucleus of iron: mass number 57, atomic number 26.

• Z = 57, N=26

• Z=26, N=31

• Z =26, N=57

• Z=31, N=26

The band of stability is above the line on the graph that has a slope of 1.

What does this indicate about the number of protons and neutrons for the majority of elements?

• There are more protons than neutrons

• There are more neutrons than protons

• There are equal numbers of protons and neutrons

Which decay is most likely to occur when there are too many neutrons in the atomic nucleus

• neutron  $\rightarrow$  proton +  $\beta-^{ }$  

• proton  $\rightarrow$  neutron +  $\beta+$  

• neutron  $\rightarrow\$  proton +  $\beta+$  

• proton  $\rightarrow$  neutron +  $\beta-$  

Tags

NGSS.HS-PS1-8

At atomic numbers of greater than 82

• Most isotopes are stable

• At least one isotope is stable

• No isotopes are stable

Tags

NGSS.HS-PS1-8

Alphas are commonly emitted by radionuclei with

• atomic numbers less than 20

• Atomic numbers less than 82 and too many protons

• Atomic numbers less than 82 and too many neutrons

• Atomic numbers greater than 82

Tags

NGSS.HS-PS1-8

Gamma radiation is emitted when

• A neutron decays into a proton and an electron and the electron is ejected from the nucleus

• A proton decays into a neutron and a positron, and the positron is ejected from the nucleus

• A neutron decays into a positron and an electron, which then annihilate

• A proton captures a low orbit electron and turns into a neutron

Tags

NGSS.HS-PS1-8

A nuclide has 90 neutrons and 60 protons, will it undergo decay?

• No, it is stable

• Yes, it will undergo beta minus decay

• Yes, it will undergo beta plus decay

• Yes, it will undergo alpha decay

Tags

NGSS.HS-PS1-8

A  $\beta^+$  particle is emitted when

• A neutron decays into a proton and an electron and the electron is ejected from the nucleus

• A proton decays into a neutron and a positron, and the positron is ejected from the nucleus

• A neutron decays into a positron and an electron, which then annihilate

• A proton captures a low orbit electron and turns into a neutron

Tags

NGSS.HS-PS1-8

 $\beta^-$ radiation has

• the mass of an electron and a charge of +1

• the mass of an electron and a charge of -1

• a mass of 4 AMU and a charge of 2+

• no mass or charge

Tags

NGSS.HS-PS1-8