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.
1 - Chemistry is a branch of science focusing on elements, reactions, and chemicals.
2 - We study chemistry to learn more about these chemicals and elements and to discover new chemicals as well as to answer questions in life about reactions.
3 - Chemistry relates to our life in various ways, from the chemicals we inhale to the basic reactions in cooking and baking.
4 - The main branches of Chemistry are Physical, analytical, biochemistry, organic and inorganic chemistry.
Hope this helps!
Answer:
Dispersion forces.
Explanation:
CO2 contains dispersion forces, and covalent bonds. It is a linear molecule, and the bond angle of O-C-O is 180 degree. O is more electronegative than C, the C-O contains polar bond with the having negative end pointing towards the O.
CO contains two C-O bonds. They cancel each other out because of the dipoles point in opposite directions. Although, CO2 contains polar bonds, it is known as a nonpolar molecule. So, the only intramolecular forces which CO2 having are London dispersion forces.
Flower and sugar
flowers in sugar water? something along these lines
We are given with the mass of pure iron that reacts with oxygen to form an oxide which has a given mass as well. the mass of oxygen reacted is 8.15-6.25 g or 1.9 grams. THen we convert the mass of the reactants to moles. Iron is equal to 0.1119 moles and oxygen is equal to 0.1188. We divide each number to the less amount. Hence iron is 1 and oxygen is approx 1. The empirical formula hence is FeO or ferrous oxide or Iron (II) oxide.
