Chick or Yolk? HELP!

[classhatching]

We are hatching chicken eggs in my grade 2 classroom. We have 24 brown eggs incubated and we are on day 10. Yesterday I candled the eggs (at day 9) and they all look the same, except for 2. Two of the eggs are definitely empty (absolutely nothing in them, light shone right through). The other 22 had a big black blob in them that moved around as I moved the eggs. No sign of veins or an eye, but the eggs are dark and I just had a regular ol' flashlight. Do you think I'm seeing the yolk or a chick?

Here's a couple of pictures:

 

[brahmabreeder]

I'm not a master but those eggs don't look good.

 

[mstricer]

It's upside down hard to tell at day ten I always leave them till at least day 14.

 

[classhatching]

So, the bigger end of the egg is supposed to be pointing up? Oops! I'm new at this! There were well defined air sacs as well, but I know that doesn't mean it's fertile.

 

[anbsmom]

They don't look like they have developed. You should be seeing veins in them at this stage.

 

[classhatching]

Also, would the yolk be that big? Why would I have 2 completely empty eggs? Where would the yolk be on those?

 

[anbsmom]

Take a look at this page: https://www.backyardchickens.com/a/candling-pics-progression-through-incubation-of-chicken-eggs