School of Chemistry and Physics Westville Campus, Durban
... School of Chemistry and Physics University of KwaZulu-Natal, Westville Campus CHEM110/195: General Principles of Chemistry May 2012 Examination ...
... School of Chemistry and Physics University of KwaZulu-Natal, Westville Campus CHEM110/195: General Principles of Chemistry May 2012 Examination ...
DRAFT AP® CHEMISTRY 2005 SCORING GUIDELINES
... Should accept oxygen gas causes splint to RE_IGNITE. The popping sound presumed the accessibility of oxygen, which is not explicit in the directions. What to do if a student claims that the splint will be extinguished? I would give the credit. Also, would accept ‘re-ignite’ for oxygen. I have a prob ...
... Should accept oxygen gas causes splint to RE_IGNITE. The popping sound presumed the accessibility of oxygen, which is not explicit in the directions. What to do if a student claims that the splint will be extinguished? I would give the credit. Also, would accept ‘re-ignite’ for oxygen. I have a prob ...
AP Chemistry:
... This Practice Exam from the 2013 international administration is provided by the College Board for AP Exam preparation. Teachers are permitted to download the materials and make copies to use with their students in a classroom setting only. To maintain the security of this exam, teachers should coll ...
... This Practice Exam from the 2013 international administration is provided by the College Board for AP Exam preparation. Teachers are permitted to download the materials and make copies to use with their students in a classroom setting only. To maintain the security of this exam, teachers should coll ...
Chapter 15. Chemical Equilibrium
... Equilibria in which all reactants and products are present in the same phase are called homogeneous equilibria. • Equilibria in which one or more reactants or products are present in a different phase are called heterogeneous equilibria. • Consider the equilibrium established when solid lead(II) chl ...
... Equilibria in which all reactants and products are present in the same phase are called homogeneous equilibria. • Equilibria in which one or more reactants or products are present in a different phase are called heterogeneous equilibria. • Consider the equilibrium established when solid lead(II) chl ...
Chemistry 11 – Course Review
... In a titration, 18.20 mL of 0.300 M Ba(OH)2 is required to react completely with a 25.0 mL sample of a solution of HNO3. Find the [HNO3]. ...
... In a titration, 18.20 mL of 0.300 M Ba(OH)2 is required to react completely with a 25.0 mL sample of a solution of HNO3. Find the [HNO3]. ...
PowerPoint
... Determining Moles of Ions in Aqueous Solutions of Ionic Compounds Problem: How many moles of each ion are in each of the ...
... Determining Moles of Ions in Aqueous Solutions of Ionic Compounds Problem: How many moles of each ion are in each of the ...
MULTIPLE CHOICE
... 50) You are given two clear solutions of the same unknown monoprotic acid, but with different concentrations. Which statement is true? A) There is no chemical method designed to tell the two solutions apart. B) It would take more base solution (per milliliter of the unknown solution) to neutralize t ...
... 50) You are given two clear solutions of the same unknown monoprotic acid, but with different concentrations. Which statement is true? A) There is no chemical method designed to tell the two solutions apart. B) It would take more base solution (per milliliter of the unknown solution) to neutralize t ...
CHEM 121 Chp 5 Spaulding
... numerically equal to what its molecular weight was in amu ◦ Just like a dozen is a quantity that contains 12 items ◦ 1 mole of C atoms = 6.02 x 1023 C atoms ◦ 1 mole of CO2 molecules = 6.02 x 1023 CO2 molecules ◦ 1 mole of H2O molecules = 6.02 x 1023 H2O molecules ...
... numerically equal to what its molecular weight was in amu ◦ Just like a dozen is a quantity that contains 12 items ◦ 1 mole of C atoms = 6.02 x 1023 C atoms ◦ 1 mole of CO2 molecules = 6.02 x 1023 CO2 molecules ◦ 1 mole of H2O molecules = 6.02 x 1023 H2O molecules ...
Thermochemistry ppt
... arbitrarily set at zero. For example, the Hf0 = 0 for the diatomic molecules H2(g), N2(g), O2(g), F2(g), Cl2(g), Br2(l), and I2(s). Many values of Hf0 have been measured. The following table lists Hf0 for some common substances. Standard heats of formation of compounds are handy for calculating h ...
... arbitrarily set at zero. For example, the Hf0 = 0 for the diatomic molecules H2(g), N2(g), O2(g), F2(g), Cl2(g), Br2(l), and I2(s). Many values of Hf0 have been measured. The following table lists Hf0 for some common substances. Standard heats of formation of compounds are handy for calculating h ...
Thermochemistry and calorimetry
... For example, the enthalpy of neutralization of a strong acid by a strong base is given by H+(aq, 1M, 298 K, 1 atm) + OH–(aq, 1M, 298 K, 1 atm) → H2O(l, 373 K, 1 atm) ΔH = —56.9 kJ mol–1 in which the abbreviation aq refers to the hydrated ions as they exist in aqueous solution. Since most thermoch ...
... For example, the enthalpy of neutralization of a strong acid by a strong base is given by H+(aq, 1M, 298 K, 1 atm) + OH–(aq, 1M, 298 K, 1 atm) → H2O(l, 373 K, 1 atm) ΔH = —56.9 kJ mol–1 in which the abbreviation aq refers to the hydrated ions as they exist in aqueous solution. Since most thermoch ...
Classifying Reactions: A good summary
... five out of the eight reactions on any given exam. 2. You earn a point for just writing the reactants in chemical form. 3. Don't forget to cancel out spectators. 4. Get familiar with the chemicals: what are they going to do, function as, how will they change. 5. Make sure you are very clear with whi ...
... five out of the eight reactions on any given exam. 2. You earn a point for just writing the reactants in chemical form. 3. Don't forget to cancel out spectators. 4. Get familiar with the chemicals: what are they going to do, function as, how will they change. 5. Make sure you are very clear with whi ...
BSPH 111 - Refresher Chemistry
... and protons, but they can have a varying number of neutrons. Within a given element, atoms with different numbers of neutrons are isotopes of that element. Isotopes typically exhibit similar chemical behaviour to each other. Isotopes are atoms of the same element with the same number of protons but ...
... and protons, but they can have a varying number of neutrons. Within a given element, atoms with different numbers of neutrons are isotopes of that element. Isotopes typically exhibit similar chemical behaviour to each other. Isotopes are atoms of the same element with the same number of protons but ...
No Slide Title
... So we need 32g of oxygen to react with 12g of carbon and 44g of carbon dioxide is formed in the reaction. © Boardworks Ltd 2003 ...
... So we need 32g of oxygen to react with 12g of carbon and 44g of carbon dioxide is formed in the reaction. © Boardworks Ltd 2003 ...
Quantitative Chemistry
... So we need 32g of oxygen to react with 12g of carbon and 44g of carbon dioxide is formed in the reaction. © Boardworks Ltd 2005 ...
... So we need 32g of oxygen to react with 12g of carbon and 44g of carbon dioxide is formed in the reaction. © Boardworks Ltd 2005 ...
Chapter 1 Chemistry and Measurement
... Homogenous Mixture A mixture that is uniform in its properties; also called a solution. For example: Saltwater Air ...
... Homogenous Mixture A mixture that is uniform in its properties; also called a solution. For example: Saltwater Air ...
Chemical Reactions
... • It is impossible to predict whether or not we will get precipitation reactions unless we know something about the physical states (especially solubility) of the various reactants and products. Here are the symbols that we use in chemical equations to say what the physical state is: ...
... • It is impossible to predict whether or not we will get precipitation reactions unless we know something about the physical states (especially solubility) of the various reactants and products. Here are the symbols that we use in chemical equations to say what the physical state is: ...
Acids-bases and Organic Review
... According to one acid-base theory, the NH3(g) molecules act as 1. an acid because they accept 3. a base because they accept H+ ions H+ ions 2. an acid because they donate 4. a base because they donate H+ ions H+ ions 67. Which substance is always a product when an Arrhenius acid in an aqueous soluti ...
... According to one acid-base theory, the NH3(g) molecules act as 1. an acid because they accept 3. a base because they accept H+ ions H+ ions 2. an acid because they donate 4. a base because they donate H+ ions H+ ions 67. Which substance is always a product when an Arrhenius acid in an aqueous soluti ...
AP Chemistry: Bonding Multiple Choice
... (A) are made up of atoms that are intrinsically hard because of their electronic structures (B) consist of positive and negative ions that are strongly attracted to each other (C) are giant molecules in which each atom forms strong covalent bonds with all of its neighboring atoms (D) are formed unde ...
... (A) are made up of atoms that are intrinsically hard because of their electronic structures (B) consist of positive and negative ions that are strongly attracted to each other (C) are giant molecules in which each atom forms strong covalent bonds with all of its neighboring atoms (D) are formed unde ...
Chapter 4 Nomenclature and Chemical Equations
... in the parenthesis tell us the states of the substances: s denotes a solid, l denotes a liquid, g denotes a gas and aq denotes an aqueous solution, i.e. a homogeneous mixture in water. Therefore, the above chemical equation informs us that solid sodium reacts with liquid water to give an aqueous ...
... in the parenthesis tell us the states of the substances: s denotes a solid, l denotes a liquid, g denotes a gas and aq denotes an aqueous solution, i.e. a homogeneous mixture in water. Therefore, the above chemical equation informs us that solid sodium reacts with liquid water to give an aqueous ...
Stoichiometry
Stoichiometry /ˌstɔɪkiˈɒmɨtri/ is the calculation of relative quantities of reactants and products in chemical reactions.Stoichiometry is founded on the law of conservation of mass where the total mass of the reactants equals the total mass of the products leading to the insight that the relations among quantities of reactants and products typically form a ratio of positive integers. This means that if the amounts of the separate reactants are known, then the amount of the product can be calculated. Conversely, if one reactant has a known quantity and the quantity of product can be empirically determined, then the amount of the other reactants can also be calculated.As seen in the image to the right, where the balanced equation is:CH4 + 2 O2 → CO2 + 2 H2O.Here, one molecule of methane reacts with two molecules of oxygen gas to yield one molecule of carbon dioxide and two molecules of water. Stoichiometry measures these quantitative relationships, and is used to determine the amount of products/reactants that are produced/needed in a given reaction. Describing the quantitative relationships among substances as they participate in chemical reactions is known as reaction stoichiometry. In the example above, reaction stoichiometry measures the relationship between the methane and oxygen as they react to form carbon dioxide and water.Because of the well known relationship of moles to atomic weights, the ratios that are arrived at by stoichiometry can be used to determine quantities by weight in a reaction described by a balanced equation. This is called composition stoichiometry.Gas stoichiometry deals with reactions involving gases, where the gases are at a known temperature, pressure, and volume and can be assumed to be ideal gases. For gases, the volume ratio is ideally the same by the ideal gas law, but the mass ratio of a single reaction has to be calculated from the molecular masses of the reactants and products. In practice, due to the existence of isotopes, molar masses are used instead when calculating the mass ratio.