Avogadro’s Number and Mole In chemistry, it is impossible to deal with a single atom or molecule because we can’t see them, count them, or weigh them. Chemists have selected a number of particles with which to work that is convenient.

3H2O has 6 hydrogen atoms and 3 oxygen atoms. However, drawing out each equation is NOT PRACTICAL. The number of atoms can be counted without having to draw it out. To mathematical find the number of elements that make up 3H2O, we multiply the 2 by the coefficient 3 to find that there are 6 H’s.

5 ATOMS

Definition of Potassium Chloride Its chemical formula is KCl, consists of one potassium (K) atom and one chlorine (Cl) atom.

Hydrogen Peroxide Two hydrogen atoms can also bond with two oxygen (O) atoms (peroxide), making the formula H2O2.

Composition of 3MgSO4

Composition of 3NaSO4

Composition of 3CH4O

There are 2 x 1022 oxygen atoms in 1 g of Epsom salt.

Sulfuric Acid, H2SO4 is a chemical compound made up of two hydrogen atom, one sulfer atom, and four oxygen atoms.

Salt (noun, “Salt”) It’s composed of a positively charged sodium atom and a negatively charged chloride atom. There are many other salts in the world, though. Copper sulfate, for instance, is also a salt. It’s made of one copper atom, one sulfur atom and four oxygen atoms.

You would have 7 hydrogen and 2 oxygen atoms.

Avogadro’s number is defined as the number of elementary particles (molecules, atoms, compounds, etc.) per mole of a substance. It is equal to 6.022×1023 mol-1 and is expressed as the symbol NA. Avogadro’s number is a similar concept to that of a dozen or a gross.

How many moles of calcium atoms does it contain? The answer is one half of a mole, because 1 mole is equal to 6.02 x 1023, so a half of a mole would be equal to 3.01 x 1023 atoms.

So if you have 5 mole, you have: 5 x (6.022 x 10^23) = 3.011 x 10^24 atoms.

calcium is 40 g, so 1 g contains 6.023 x 10^23/40 atoms = 1.506 x Use this page to learn how to convert between grams Calcium Chloride and mole.

114.818 grams

5.00 moles

In order to convert the moles of a substance to grams, you will need to multiply the mole value of the substance by its molar mass.

The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles NH4Cl, or 53.49146 grams.

0.375 moles

18.02 grams

15.998 grams

44.01g

∴ 2 N molecules of CO2 has molecular mass =44×2=88g.

For carbon dioxide, CO2, one carbon atom contributes 12.01 g/mol, the two oxygens together contribute (2)(16.00) = 32.00 g/mol. The molar mass is then 12.01 + 32.00 = 44.01 g/mol.

The answer is 24 g.