#5» FeC2O4⋅2H2O [iron(II) oxalate dihydrate]. of C14H18N2O5 (the numbers are subscripts) and i need to find the number of atoms of carbon. Let’s consider the following example. The atomic weight of phosphorus is 30.97. Now you know that atomic number = number of protons, and mass number = number of protons + number of neutrons. 1 C atom = 12.011 amu. For instance, let consider potassium sulfate. The exponents on the subshells should add up to the number of bonds and lone pairs. For example, the molar mass of NaCl can be calculated for finding the atomic mass of sodium (22.99 g/mol) and the atomic mass of chlorine (35.45 g/mol) and combining them. There are two atoms of oxygen. It can also used for calculating the number of atoms or molecules present. In the same way, HCl has one atom of Hydrogen (H) and one atom of Chlorine (Cl). Obtain the atomic masses of each element from the periodic table and multiply the atomic mass of each element by the number of atoms of that element. Calculate the number of hydrogen atoms there are in 75.00 grams of C6H14O4. $\begingroup$ I'm not sure I understand what that means, but: you know the number of atoms of the required type contained in each molecule of the compound, and you can figure out the number of molecules of the compound from the data you are given. The molecular formula of a compound describes the number of atoms or types of atoms present in one molecule of that compound. Have them look at each of their formulas and determine the number of atoms of each element, the total number of atoms, and the total number of elements in each compound. 2.378x10^-4 molec. Fluorine has 1 bond and 3 lone pairs giving a total of 4, making the hybridization: sp3. An empirical formula tells us the relative ratios of different atoms in a compound. For example, the molecular formula for water is H 2 O. Each molecule of potassium sulfate comprises two atoms of potassium (K), an atom of sulfur (S), and four atoms of oxygen (O). To calculate the coordination no. Ask Question Asked 3 years, 3 months ago. 0.5 moles C 6 H 14 O 4 x 14 moles H/mole C 6 H 14 O 4 x 6.02x10 23 atoms/mole = 4.214x10 24 hydrogen atoms. c) 2.08 x 10 21 Se atoms. Thanks for the clarification P.S All the number … K 2 SO 4 is the chemical formula of potassium sulfate. It’s like saying we have 2 of H2O. Calculate the mass in grams of the following: a) 4.45 x 10 19 Ag atoms. For example, the molecular formula for water is H2O. Calculate the molecular formula if the molar mass of the compound is 300 g/mol. Similarly, we can calculate the total number of atoms in 1 mole of sodium chloride. Active 3 years, 3 months ago. To calculate the molar mass of a compound with multiple atoms, sum all the atomic mass of the constituent atoms. Fourth, convert that to mols: Formula to calculate molecular formula. So that means 4 × 2 (we covered that for example #3 above). 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