About Formulas Types of Bonding Ionic Covalent Metallic
![About Formulas About Formulas](https://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-1.jpg)
About Formulas
![Types of Bonding Ionic Covalent Metallic • Occurs between metals & nonmetals • Electrons Types of Bonding Ionic Covalent Metallic • Occurs between metals & nonmetals • Electrons](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-2.jpg)
Types of Bonding Ionic Covalent Metallic • Occurs between metals & nonmetals • Electrons are transferred • Form crystal lattice • Na. Cl • Ca. Br 2 • Occurs between nonmetal • Electrons are shared • Form molecules • H 2 O • C 6 H 12 O 6 • Occurs between metals • Electrons are shared • Form crystal lattice • Al • Fe
![Metals vs. Nonmetals n Most of the elements in the periodic table are metals. Metals vs. Nonmetals n Most of the elements in the periodic table are metals.](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-3.jpg)
Metals vs. Nonmetals n Most of the elements in the periodic table are metals. • Except for H, everything to the left of the staircase is a metal n Nonmetals are located to the right of the staircase.
![Crystal Lattice vs. Molecule n n Molecule: Discrete unit, definite number of atoms. All Crystal Lattice vs. Molecule n n Molecule: Discrete unit, definite number of atoms. All](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-4.jpg)
Crystal Lattice vs. Molecule n n Molecule: Discrete unit, definite number of atoms. All molecules of a given compound are identical. Exact formula. Crystal Lattice: Regular, repetitive, 3 -D arrangement of atoms, ions, or molecules. No set size. Not perfect. No two exactly alike. • Formula gives smallest whole number ratios. (Formula unit). “Exact” formulas NOT useful.
![2 -D repetitive patterns 2 -D repetitive patterns](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-5.jpg)
2 -D repetitive patterns
![Na. Cl Crystals: 3 -D repetitive patterns Na. Cl Crystals: 3 -D repetitive patterns](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-6.jpg)
Na. Cl Crystals: 3 -D repetitive patterns
![](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-7.jpg)
![Formulas n n Tell the type & number of atoms in a compound. Microscopic Formulas n n Tell the type & number of atoms in a compound. Microscopic](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-8.jpg)
Formulas n n Tell the type & number of atoms in a compound. Microscopic level: imagine 1 atom, molecule, or formula unit. • Formula gives atom ratios. n Macroscopic level: imagine working in the lab • Formula gives mole ratio
![Formulas n Ex: 2 H 2 O can mean • 2 molecules of water Formulas n Ex: 2 H 2 O can mean • 2 molecules of water](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-9.jpg)
Formulas n Ex: 2 H 2 O can mean • 2 molecules of water • 2 moles of water. 2 H 2 O molecules have 4 hydrogen atoms & 2 oxygen atoms. 2 Moles of H 2 O molecules have 4 moles of hydrogen atoms & 2 moles of oxygen atoms.
![Ionic vs. Covalent Formulas n By looking at the type of atoms, we can Ionic vs. Covalent Formulas n By looking at the type of atoms, we can](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-10.jpg)
Ionic vs. Covalent Formulas n By looking at the type of atoms, we can decide if the substance is an ionic compound or a molecular (covalent) compound. Molecular compounds usually have all nonmetals. Ionic compounds usually have metal + nonmetal.
![Empirical Formula n n n Smallest whole number ratio of the elements in the Empirical Formula n n n Smallest whole number ratio of the elements in the](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-11.jpg)
Empirical Formula n n n Smallest whole number ratio of the elements in the compound. Ionic compounds have only empirical formulas. Covalent compounds have empirical and molecular formulas. They can be the same or different.
![Molecular Formulas n n n For covalent (molecular) compounds. Give the exact composition of Molecular Formulas n n n For covalent (molecular) compounds. Give the exact composition of](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-12.jpg)
Molecular Formulas n n n For covalent (molecular) compounds. Give the exact composition of the molecule. Molecular compounds have both empirical and molecular formulas. They can be the same or different.
![Say everything you can about: Na. Cl Ionic, empirical CH 4 C 6 H Say everything you can about: Na. Cl Ionic, empirical CH 4 C 6 H](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-13.jpg)
Say everything you can about: Na. Cl Ionic, empirical CH 4 C 6 H 6 Covalent, molecular Covalent, empir. , molec? C 8 H 18 Covalent, molecular Ca. Br 2 Ionic, empirical CF 4 Covalent, empirical, molecular? KI Ionic, empirical Cu. SO 4 5 H 2 O Ionic, empirical C 6 H 12 O 6 Covalent, molecular Be. SO 4 Ionic, empirical C 2 H 4 Cl 2 Covalent, molecular
![Say everything you can about PH 3 C 2 H 4 Al 2 O Say everything you can about PH 3 C 2 H 4 Al 2 O](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-14.jpg)
Say everything you can about PH 3 C 2 H 4 Al 2 O 3 Sr. I 2 NF 3 H 2 Se CH 3 OH Si. O 2 H 2 O 2 CCl 4 Xe. F 4 P 4 O 10
![Empirical Formulas from % Composition n n n Convert to mass. Convert to moles. Empirical Formulas from % Composition n n n Convert to mass. Convert to moles.](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-15.jpg)
Empirical Formulas from % Composition n n n Convert to mass. Convert to moles. Divide by small. Multiply ‘til whole. Note 1: last step not always used. Note 2: sometimes you start at step 2, if they give analysis data in grams.
![Compound: 63. 52% Fe & 36. 48% S n Convert to grams: Assume 100 Compound: 63. 52% Fe & 36. 48% S n Convert to grams: Assume 100](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-16.jpg)
Compound: 63. 52% Fe & 36. 48% S n Convert to grams: Assume 100 g sample-size to make math easy. • 63. 52 g Fe and 36. 48 g S n Convert to moles: Divide by atomic masses. 63. 52 g Fe / 55. 8 g Fe/mol Fe = 1. 138 mol Fe 36. 48 g S / 32. 1 g S/mol S = 1. 136 mol S
![Compound: 63. 52% Fe & 36. 48% S n Divide by small: This is Compound: 63. 52% Fe & 36. 48% S n Divide by small: This is](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-17.jpg)
Compound: 63. 52% Fe & 36. 48% S n Divide by small: This is where you take the ratio. • 1. 136 and 1. 138 are essentially the same. Divide both by 1. 136 and get 1 for each. • Empirical formula is Fe. S.
![26. 56 % K, 35. 41% Cr, & remainder O n Assume 100 -g 26. 56 % K, 35. 41% Cr, & remainder O n Assume 100 -g](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-18.jpg)
26. 56 % K, 35. 41% Cr, & remainder O n Assume 100 -g sample size. • 26. 56 g K • 35. 41 g Cr • 38. 03 g O n Convert to moles. 26. 56 g K / 39. 1 g K/mol K = 0. 679 mol K 35. 41 g Cr / 52. 0 g Cr/mol Cr = 0. 681 mol Cr 38. 03 g O / 16. 0 g O/mol O = 2. 38 mol O
![26. 56 % K, 35. 41% Cr, & remainder O n Divide by small: 26. 56 % K, 35. 41% Cr, & remainder O n Divide by small:](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-19.jpg)
26. 56 % K, 35. 41% Cr, & remainder O n Divide by small: • 0. 679 and 0. 681 are essentially the same. • Much smaller than 2. 38. • Divide each by 0. 68 • K: 1, Cr: 1, O: 3. 5 KCr. O 3. 5? No dec’s n n Multiply ‘til whole: K 2 Cr 2 O 7. Multiply all three by 2, doesn’t change relationship.
![Relationship between empirical and molecular formulas n n n The molecular formula is a Relationship between empirical and molecular formulas n n n The molecular formula is a](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-20.jpg)
Relationship between empirical and molecular formulas n n n The molecular formula is a whole number multiple of the empirical formula. Molec. Formula = n (Empirical Form. ) n is a small whole number, which multiplies the subscripts. Sometimes, n = 1.
![Molecular Formula n n If you know the empirical formula and the molar mass, Molecular Formula n n If you know the empirical formula and the molar mass,](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-21.jpg)
Molecular Formula n n If you know the empirical formula and the molar mass, you can find the molecular formula. Step 1: Find the mass of the empirical formula. Step 2: Molar mass Empirical mass = small whole number, n Step 3: Multiply the subscripts in the empirical formula by n.
![Finding Molecular Formulas n n n Find the molecular formula for the substance whose Finding Molecular Formulas n n n Find the molecular formula for the substance whose](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-22.jpg)
Finding Molecular Formulas n n n Find the molecular formula for the substance whose empirical formula is CH and whose molar mass = 78. 0 g Step 1: Empirical mass = 13. 0 g Step 2: Molar mass = n = 78. 0/13. 0 Empirical mass n = 6. Step 3: 6 X subscripts in CH = C 6 H 6.
![What can you say about Cu. SO 4 5 H 2 O? n n What can you say about Cu. SO 4 5 H 2 O? n n](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-23.jpg)
What can you say about Cu. SO 4 5 H 2 O? n n n It’s a hydrated salt. For every mole of Cu. SO 4, there are 5 moles of water. If it’s heated, it dries out. The water goes into the air and you’re left with the anhydrous salt, Cu. SO 4 5 H 2 O Cu. SO 4 + 5 H 2 O
![Cu. SO 4 5 H 2 O Cu. SO 4 + 5 H 2 Cu. SO 4 5 H 2 O Cu. SO 4 + 5 H 2](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-24.jpg)
Cu. SO 4 5 H 2 O Cu. SO 4 + 5 H 2 O n The mole ratio in the formula can be used to predict how much water would be given off by any size sample. • If you had 2 moles of Cu. SO 4 5 H 2 O, how much water would you lose on heating? • If you had 5 moles of Cu. SO 4 5 H 2 O, how much water would you lose?
![Percent Water in Cu. SO 4 • 5 H 2 O n Step 1: Percent Water in Cu. SO 4 • 5 H 2 O n Step 1:](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-25.jpg)
Percent Water in Cu. SO 4 • 5 H 2 O n Step 1: Calculate the formula mass. • Mass of salt + Mass of water n n Percent = (Part/Whole) X 100% % H 2 O = Mass H 2 O/Formula Mass X 100 % % composition from the formula
![Percent Water in Cu. SO 4 • 5 H 2 O 12. 00 grams Percent Water in Cu. SO 4 • 5 H 2 O 12. 00 grams](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-26.jpg)
Percent Water in Cu. SO 4 • 5 H 2 O 12. 00 grams of Cu. SO 4 • 5 H 2 O are heated gently. The final mass after repeated heatings is 7. 68 grams. What is the % of water? Mass of H 2 O = (12. 00 – 7. 68) = 4. 32 g Percent H 2 O = 4. 32 g X 100% = 36% 12. 00 g Percent composition from experimental data
![Cu. SO 4 x. H 2 O Cu. SO 4 + x. H 2 Cu. SO 4 x. H 2 O Cu. SO 4 + x. H 2](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-27.jpg)
Cu. SO 4 x. H 2 O Cu. SO 4 + x. H 2 O n n Use experimental data to find x: 12. 00 grams of Cu. SO 4 • 5 H 2 O are heated gently. (Hydrated salt. ) 7. 68 g = mass anhydrous salt remaining = mass Cu. SO 4. Mass of H 2 O = (12. 00 – 7. 68) = 4. 32 g
![Cu. SO 4 x. H 2 O Cu. SO 4 + x. H 2 Cu. SO 4 x. H 2 O Cu. SO 4 + x. H 2](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-28.jpg)
Cu. SO 4 x. H 2 O Cu. SO 4 + x. H 2 O n n Note: moles of Cu. SO 4 & moles of H 2 O can be determined. Have grams already. • Convert to moles • Divide by small • Multiply ‘til whole.
![Cu. SO 4 x. H 2 O Cu. SO 4 + x. H 2 Cu. SO 4 x. H 2 O Cu. SO 4 + x. H 2](http://slidetodoc.com/presentation_image_h/b9f0b53aa35ed91b07a4521c9fec5314/image-29.jpg)
Cu. SO 4 x. H 2 O Cu. SO 4 + x. H 2 O n n 7. 68 g Cu. SO 4 / 159. 6 g/mol = 0. 04812 mol Cu. SO 4 4. 32 g H 2 O / 18. 0 g/mol = 0. 240 mol H 2 O Divide by small, which is 0. 04812 Cu. SO 4 5 H 2 O
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