Chemistry Learning Center

230 Davenport Hall Chemistry TAs available from 9 am –

5pm Mondays – Fridays. Chemistry 202 TAs in the CLC:

Mondays: 11am-1pm, 3pm-5pm Wednesdays: 3pm-5pm Thursdays: 3pm-5pm

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Lon-Capa

1st HW assignment due Friday, 9/4, 5 pm. It is open now.

1st Quiz due Sunday, 9/6 by 10 pm. It will open Wednesday, 9/2 at 5 pm.

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For Wednesday Continue working on Lon-Capa. Finish reading Chapter 4 and doing

the Chapter 4 homework. See me or email me if there are

any questions or concerns.

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A Complex ProblemBaking soda (sodium bicarbonate) decomposes upon heating to form sodium carbonate, water vapor, and carbon dioxide. Sodium carbonate does not decompose further at this temperature.

You have a 10.00 g mixture of baking soda and sodium carbonate and heat it until completion. After heating you are left with 8.97 g of solid.

Determine the mass percent of baking soda in the original mixture.

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Chapter 3: #114Consider a gaseous binary compound with a molar mass of 62.09 g/mol. When 1.39 g of this compound is completely burned in excess oxygen, 1.21 g of water is formed.Determine the formula of the compound.

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Chapter 3: #112A 2.25-g sample of scandium metal is reacted with excess hydrochloric acid to produce 0.1502 g hydrogen gas.

What is the formula of the scandium chloride produced in the reaction? 6

Formulas for Ionic Compounds are Empirical Formulas

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NaCl Dissolves

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p1299

Solubility Rules

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p13011

Precipitation Reactions Know how to use the solubility

rules (you will be given them on the exam).

Know how to write equations from reactants (ionic reactants).

Understand what solutions “look” like at a very magnified level.

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Clicker Question When lead(II) nitrate and potassium iodide are mixed, which are the possible products?

1. PbI2. PbI23. K(NO3)2

4. KNO3

a) 1 & 3 b) 1 & 4 c) 2 & 4 d) 2 & 3

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