Question

Which of the following compounds is a molecule?
NaCl

MgBr2

H2

AlCl3 Which of the following compounds is a molecule?
NaCl

MgBr2

H2

AlCl3 @Biology

Answer 1

Do you understand the difference between covalent and ionic bonds? :) You can identify the molecule here from the bonds they form.

Answer 2

annnnd?

Answer 3

Lol, I'm not going to tell you the answer, I want you to work it out!

Answer 4

ok. well no medal for you :)

Answer 5

That's fine, I have my fair share.. I'll give you a medal though if you put down the right answer :D

Answer 6

well at least tell me more\

Answer 7

Okay :) let me think of a good way to put it..

Answer 8

NaCl

Answer 9

thx bro! medal for you

Answer 10

Uhh Haze, that's wrong.

Okay so:
Ionic bonds result when electrons are tranfered between atoms. They don't form a discreet 'molecule'
Covalent bonds result when valence electrons are shared between atoms. Molecules with covalent bonds.. well are molecules.
So to transfer elections the atoms must have opposite charges (ionic) and to be covalent and 'share' electrons they are usually of similar charge. There is only one thing here that has two atoms with similar charge :) Look at their relative positions on the periodic table..
If they are on opposite ends of the table the will have opposite charges and so will be ionically bonded.
Periodic table: http://openstudy.com/#/updates/4ebc9f43e4b021de86e1e902

Answer 11

Na and Cl, because they have opposite charges will form ionic bonds (and will exist as a lattice structure) and so NaCl is not a molecule. Here are some cool pictures of lattices: http://departments.kings.edu/chemlab/animation/nacl.html

Answer 12

H2 is the molecule. all others are salts.