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Which of the two objects or substances has the higher energy? Answer with a number, 1 or 2.   A methane molecule, CH4, in the stratosphere or A CH3 molecule and a hydrogen atom formed from breaking one of the carbon-hydrogen bonds in a CH4 molecule? [dog9]   A water molecule moving at 1.63 x 102 mi/hr or the same water molecule moving at 1.81 x 103 mi/hr. [dog10]   Iodine solid or Iodine gas (assume the two systems are at the same temperature) [dog11]   A water molecule moving at 1.63 x 103 Mi/hr or a uranium hexafluoride, UF6, molecule moving a the same velocity. [dog12]

The mass (in grams) of an atom is very small. The mass of the protons, neutrons, and electrons that make it up are smaller yet. In order to make these small values easier to use, chemists devised what?

The earth weighs about 1 x 1021 tons. Convert this to gigagrams. (There are 2000 pounds to a ton).

Write the names for each of the following compounds. CdI2  [ann5] Ca3P2  [ann6] Au(OH)3  [ann7]   FeCl2  [ann8]

Write the names for each of the following compounds. ClO2  [ann1] C2H6  [ann2] HF  [ann3] BrCl  [ann4]

Are the electrons in the following redox reactions transferred completely form the atoms of one element to the atoms of another or are they only partially transferred? Answer partial or complete.   2K + F2 –> 2KF  [ans9]   2H2 + O2 –> 2H2O     [ans10]   Ca + Cl2 –> CaCl2      [ans11]   4 Cu + O2 –> 2Cu2O   [ans12]

For the following equation determine the oxidation number for each atom in the equation and identify whether the reaction is a redox reaction or not. If the reaction is redox, identify what is oxidized, what is reduced, the oxidizing agent, and the reducing agent. If it is not a redox reaction, put NA those answer blocks.   2Na + 2H2O–> 2NaOH + H2   Reactants Oxidation Numbers:   Na      [ann1]   H        [ann2]   O         [ann3]   Product Oxidation Numbers   Na      [ann4]   H         [ann5]   O         [ann6]   Is this a redox reaction?       [ann7]   If it is, what is element is oxidized?  [ann8]   What element is reduced?     [ann9]   What element is the oxidizing agent?        [ann10]   What is the reducing agent?       [ann11]

While you are at rest, your brain gets about 15% by volume of your blood. If your body contains 5.2 L of blood, how many liters of blood are in your brain at rest? How many quarts?   Liter  [answ3]   Quarts   [answ4]

Write the chemical formula for a compound made from hydrogen and sulfur. Name the compound. Formula  [joe7] Name  [joe8] c. Is it an ionic or molecular compound?  [joe9]

The Lewis structure indicates that methane assumes a tetrahedral molecular shape. Why is this true?