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Stoichiometry

Empirical formulae - the uses

A 1.000g sample of an unknown hydrocarbon containing only carbon and hydrogen is burned in excess oxygen to yield carbon dioxide and water. The masses of CO2 and H2O are 2.994g and 1.635g, respectively. What is the empirical(simplest) formula for this compound?

Finding molarity and the reactions and productions of a balanced equation

1.) What is the molarity of a solution made by dissolving 25.6 g of KOH (5601 g/mol) in enough water to make 3.00 L of solution? 2.) 2 Fe + 3 Cl2 ------> 2FeCl3 How many moles of Fe are needed to produce 76.4 g of FeCl3 (162.3 g/mol)? How many grams of Fe (55.8 g/mol) are needed to react with 123 g or cl2 (71.0 g/mo

Multiple choice question about the relationship between Q and Kp.

If the value of Q is greater than Kp, then a. the system is in equilibrium b. the reaction will proceed to the right until equilibrium is established c. a catalyst is necessary to achieve equilibrium d. the reaction will go left or right depending on the reaction stoichiometry e. the reaction will proceed to

Chemistry multiple choice questions (chem-2)

1. A collection of atoms, molecules, or ions that contains Avogadro's number of these items is called what? 2. The initial substances that undergo change in chemical reaction are called what? 3. The law that states that atoms are neither created nor destroyed in a chemical reaction, but may be rearranged, is called what? 4. T

Average Molar Atomic Weight of Chlorine

What is the average molar atomic weight of chlorine, if the natural abundance of Cl-35 and Cl-37 isotopes are 75.4 molar % and 24.6 molar %, respectively? M(Cl-35) = 34.969 g/mole M(Cl-37) = 36.966 g/mole.

Determining the formula of a hydrate.

When all of the water of hydration was driven off of 4.32g of a hydrate of compound Z, the residue, the anhydrous form of Z, had a mass of 3.09g. What is the formula of the hydrate (using the symbol Z as part of it)? The formula mass of Z is 90.0

Mixture- identity of metals

When 8.900 g of a mixture of an alkali metal chloride (XCl) and an alkaline earth chloride (YCl2) was dissolved in 150.0g of water, the freezing point of the resultant solution was -4.42C. Addition of an excess of aqueous AGNO3 to the solution yielded a white precipitate with a mass of 27.575 g (This white precipitate would be

Products of Radioactive Decays

What are the products of the following radioactive decays? A. Alpha emission by: 162 Re 75 B. Beta emission by: 188 W 74 C. Positron emission by: 165 Ta 73

Uses of mercury

1. Find out 2 or 3 uses for mercury. 2. For each use find out why mercury was chosen for the job 3. What are the dangers from using mercury.

Converting grams to kilojoules.

Burning 2.00g of propane, C3H8, produces 99.78 kJ of energy. How much energy is produced when one mole of the propane burns?