PPT-Molecular Formula

Represents the actual number of atoms of each element in compound Not necessary for ionic compounds Necessary for covalent compounds The molecular formula for water is H 2 O. Structural Formula Molecular Formula 16 13 ClN O Molecular weight 28474 CAS registry number 439 14 DESCRIPTION Diazepam is a benzodiazepine derivative It is a colourless crystalline compound insoluble in water PHARMACOLOGY Pharmacokinetics Absoprtio . vs. . Empirical Formula. Different compounds can have the . same. empirical formula. but . different. molecular formulas. .. Empirical . Formula is a . reduced. . form of Molecular formula . Molecular Formula and Empirical Formula. Molecular Formulas. Let’s use those mole conversions!. Empirical formula . tells you the lowest ratio of atoms within a molecule. Molecular formula . tells you the actual ratio of atoms within a molecule. Q- a compound is found to contain the following % by mass: 69.58% Ba, 6.090% C, 24.32% O. What is the simplest (i.e. empirical) formula?. Step 1. : imagine that you have 100 g of the substance. Thus, % will become mass in grams. E.g. 69.58 % Ba becomes 69.58 g Ba. (Some questions. You should know this for the quiz!. Empirical and Molecular Formulae. Empirical Formula. If needed, change % to g.. Do . a molar conversion to change from . g. mol. Divide each of these numbers by the smallest number. Do Now: from last years regents. Chemical Formulas. Tell . type. & . number. atoms in compound. Microscopic level: . Formula gives atom ratios. Macroscopic level: . Formula gives mole ratios. EXAMPLE. Chemistry GT 3/20/15. Drill. Calculate the percent composition of Na. 2. SO. 4. .. HW: Molecular Formula WS (pg. 4). MM. =142.05 . g. /mol. 32.37% Na, 22.58% S, 45.05% O. Chem. Joke of the Day. The photon checked into a hotel. What did it say when the bellhop asked for its bag?. Lecture Presentation. Chapter 3. Molecules, Compounds, and Chemical Equations. How Many Different Substances Exist? . Elements combine with each other to form . compounds. . . The great diversity of substances that we find in nature is a direct result of the ability of elements to form compounds. . Due at end of Period. The compound . benzamide. has the following percent composition. What is the empirical formula? . C . = 69.40 % H= 5.825 % O = 13.21 % N= 11.57 % . 2. A . component of protein called serine has an approximate . Unit 3 – Stoichiometry. Which element does the PES spectrum above represent?. Draw the Bohr Model of this element.. Is there anything in the PES data for this element that requires revision of the Bohr model? . 2 H. 2. + O. 2. .  2 H. 2. O. Read as “2 moles of hydrogen combined with 2 moles of oxygen yield 2 moles of water” . So what’s a mole??. Definitions. Mole- unit of measurement defined by the amount of substance that contains the same number of particles in 12 g of a Carbon-12 atom. I. Percent Composition. Think about this:. How would you find the percent of boys in our class?. # of boys (part)____. x 100% . Total # of students (whole). I. Percent Composition. . Lowest whole # ratio . H. 2. O. 2. (hydrogen peroxide) is it a empirical Formula?. No, you can reduce it to HO . . H. 2. O. 2 . is the molecular formula. Molecular formula shows the way the molecule is actually found in nature.. Determining Molecular Formulas. Calculate the molecular formula of a compound whose molar mass is 60.0 g/mol and has an empirical formula of CH4N.. What you need:. Empirical Formula. Molar Mass. Calculate the molar mass of the empirical formula.