^ [nitpick] It really doesn’t make sense to call each “na” a gram. Maybe replace “the 16 grams of sodium” with “16 sodium atoms”? It usually said something like this:
Sixteen sodium atoms walk into a bar… followed by Batman. And then sing the song after a puzzled look. [/nitpick]
I was going to guess Elon Musk.
What’s the difference between a well dressed man on a unicycle and a poorly dressed man on a bike?
Attire.
How does Snoop keep his whites super-white?
With blee-ach.
And in the non-joke vein, what’s blue and smells like paint?
Blue paint.
Professor Pavlov is sitting in a bar when he hears a phone ring. He jumps up and exclaims, “Oh, crap! I forgot to feed the dogs!”
Stolen from Car Talk:
What’s the difference between a snake and a Yugo?
You can count the rattles on a snake.
I heard the analogue to this.
How do you say four people drowned in Spanish?
Quattro Cinco
What’s gray and yellow and gray and yellow and gray and yellow and gray and yellow and gray and yellow?
An elephant rolling down a hill with a daisy in its mouth.
Q. What’s invisible and smells like carrots?
A. Bunny farts.
Q. Why do farts stink?
A. So that deaf people can appreciate them, too.
A skeleton walks into a bar and asks for a glass of beer and a mop.
That’s 16 atoms.
What’s the difference between a bassoon and an accordion?
…
…
A bassoon burns faster, but an accordion burns hotter.
A classic:
a: Knock knock
b: Who’s there?
a: Interrupting cow
b: inter… a: MOOOOO!
Q. What do you call a groupie who hangs out with bands?
A. A drummer.
I stole this one from Benny Hill:
“We call our little dog Teeny, cause he’s the teeniest.
We call our big dog Meany, cause he’s the meaniest.
And we call the last dog Liberace, cause he’s the peein’est!”
Another one shamelessly stolen from Benny Hill:
“Why do graveyards have walls?
'Tis queer beyond a doubt.
The people on the outside don’t want to come in,
And the people on the inside surely can’t come out!”
One more Benny Hill one:
“Please don’t blame our doggy.
It’s not his fault at all.
Someone left a wet umbrella
Standing in the hall.”
Leading on to: Have you heard about the extremely popular cemetery? People are dying to get in.
That joke did make me laugh. Clever 
How did the skunk contact his girlfriend?
He used his smell phone.
What did one eye say to the other?
Between you and me, something smells.
A boy went to a fish market and bought two fish, but when he came home, he had three. How can that be?
He got two herrings - and one smelt.
Meh. My jokes stink.
What do you call a deer with no eyes?
No idea.
What do you call a deer with no eyes and no legs?
Still no idea.
What time was it when John Denver recorded, “Take Me Home, Country Roads”?
Almost seven.
What is Harry Potter’s favorite method of getting down a hill?
Walking … jk rolling