Which is made of one kind of atom:carbon,water,oxygen,milk?

Answer 1

Carbon and oxygen are both atoms - check the periodic table for a chart which tells you all of the atoms.

Water is a compound - hydrogen and oxygen chemically bonded together to form water. A pure compound has a constant composition with fixed ratios of elements.

Milk is a mixture. A mixture is a combination of two or more substances that are not chemically joined. A mixture can be physically separated into pure compounds or elements.

Hope this helps!

Answer 2

Carbon is only made of the carbon atom;

Oxygen is only made of oxygen atoms, but it's diatomic in nature which means that it usually exists as a molecule containing 2 atoms of oxygen (hence, O2);

(Pure) Water is a molecule that contains 2 atoms of Hydrogen for every atom of Oxygen; if the water isn't pure (distilled) it can contain lots of stuff!

Milk is a mixture of several different atoms, and is also a complex mixture of proteins, amino acids and water.

Answer 3

For this kind of question, ask yourself which ones you can find on the periodic table. The periodic table only lists elements (made of one kind of atom) and not compounds. You can find carbon at number 6 and oxygen at number 8. Water isn't on there (because it's hydrogen and oxygen together) and milk isn't on the periodic table because it's made of a whole bunch of different kinds of molecules.

Answer 4

Oxygen - O2

Answer 5

C=carbon
O=oxygen
H2O=water.