HomeworkRead section 4.4Answer questions 26 & 27 on page 107.

What you will learn today:

What you will learn today:

What you will learn today:

•nuclear reaction•radioactive decay•alpha particle•beta particle•gamma ray

Chemistry is all about the

electrons.

The nucleus doesn’t get involved in chemical reactions.

But there are such things as nuclear reactions.

In the late 1800’s, scientists discovered radioactivity.

In the late 1800’s, scientists discovered radioactivity.

In the late 1800’s, scientists discovered radioactivity.

In the late 1800’s, scientists discovered radioactivity.

In the late 1800’s, scientists discovered radioactivity.

In the late 1800’s, scientists discovered radioactivity.

In the late 1800’s, scientists discovered radioactivity.

In the late 1800’s, scientists discovered radioactivity.

In the late 1800’s, scientists discovered radioactivity.

In the late 1800’s, scientists discovered radioactivity.

So what is radioactivity?

In the late 1800’s, scientists discovered radioactivity.

Radioactive source in a lead box

screen

So what is radioactivity?

positive

negative

screen

So what is radioactivity?

positive

negative

So what is radioactivity?

Alpha (α)+2

positive

negative

So what is radioactivity?

Alpha (α)+2

positive

negative

So what is radioactivity?

Alpha (α)+2

positive

negative

Beta (β)-1

So what is radioactivity?

Alpha (α)+2

positive

negative

Beta (β)-1

So what is radioactivity?

Alpha (α)+2

positive

negative

Beta (β)-1

Gamma (γ)0

So what is radioactivity?

alpha particle

α 2 protons + 2 neutrons

mass ≈ 4 AMUcharge = +2

So what is radioactivity?

beta particle

β1 electronmass ≈ 1/1000 AMUcharge = -1

So what is radioactivity?

gamma ray

γpure energymass = 0charge = 0

So what is radioactivity?

226 88Ra

So what is radioactivity?

mass number 226 atomic number 88Ra

So what is radioactivity?

226 88 Ra→

So what is radioactivity?

226 222 88 86 Ra→ Rn

So what is radioactivity?

226 222 4 88 86 2Ra→ Rn+ He

So what is radioactivity?

226 222 4 88 86 2Ra→ Rn+ Heradium-226

So what is radioactivity?

226 222 4 88 86 2Ra→ Rn+ Heradium-226 radon-222

So what is radioactivity?

226 222 4 88 86 2Ra→ Rn+ Heradium-226 radon-222 alpha particle

So what is radioactivity?

radium-226 radon-222 alpha particle

So what is radioactivity?

238 234 4 0 92 90 2 0U→ Th+ He + 2 γ

So what is radioactivity?

238 234 4 0 92 90 2 0U→ Th+ He + 2uranium-238 thorium-234 alpha particle gamma ray

γ

So what is radioactivity?

uranium-238 thorium-234 alpha particle gamma ray

So what is radioactivity?

14 14 0 6 7 -1C→ N + β

So what is radioactivity?

14 14 0 6 7 -1C→ N + βcarbon-14 nitrogen-14 beta particle

So what is radioactivity?

So what is radioactivity?

So what is radioactivity?

So what is radioactivity?

HomeworkRead section 4.4Answer questions 26 & 27 on page 107.