Answer:
Explanation:
To solve this problem, we must understand the relationship between mass of a substance and the number of atoms.
Atoms are the smallest indivisible particles of any matter. A substance can be made up of several number of atoms in their space.
The mass of any substance is a function of the amount of atoms its contains.
The mass of a substance is related in chemistry to the amount of atoms its contains using the parameter called the number of moles.
A mole is the amount of substance that contains the Avogadro's number of particles. This number is 6.02 x 10²³ particles. The particles here can be protons, neutrons, electrons, atoms e.t.c.
Now,
Number of moles = 
Molar mass of copper = 63.6g/mole
Number of moles =
= 0.03mole
Since 1 mole of a substance contains 6.02 x 10²³atoms
0.03 mole of copper will contain 0.03 x 6.02 x 10²³atoms
= 1.89 x 10²² atoms
He needs to add 1.89 x 10²² atoms to make 2g of the sample.
An organic compound in which a carbonyl group is bonded to two different carbon atoms is a ketone. The ketones are organic compounds in which a carbonyl group (C=O) is bonded to two carbon atom. A carbonyl group is a carbon-oxygen double bond. Ketones are of great importance in industry and in biology, <span>as solvents, polymer precursors, and pharmaceuticals.</span>
I have heard they can use hair is stocking or nets to absorb the oil out of the water
It will be easier to answer if you show the choices.