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Explain why the temperature of a substance does not change as it melts, even though heat is being added.

Hydrogen bonding is a special type of dipolar force that occurs when hydrogen is bonded to what 3 possible elements? (Use appropriate symbols for the elements. Use commas to separate the symbols)

Determine the oxidation number of the underlined element in the following ion. Be sure to indicate if the oxidation number is positive or negative. (HSO2)-1

Which of the following choices best classifies the following reaction:  H2O  + CO2  H2CO3 a. combination b. single replacement c. decomposition d. double replacement  e. redox f.  nonredox

According to the chemical naming system, which name is incorrect? Formula:                 Name: SnCl4               tin chloride SCl2                       sulfur dichloride Mg(NO3)2        magnesium nitrate Na2(CO3)         sodium carbonate FeBr2               iron (II) bromide  

Which of the following choices best classifies the following reaction:  Na2S+   Pb(NO3)2    PbS  +  2 Na(NO3) a. combination b. single replacement c. decomposition d. double replacement  e. redox f.  nonredox

Balance the equation below by placing the correct coefficients in the blanks. Your response should list the coefficients in order from left to right, separated only by commas; no spaces. If no coefficient belongs in a blank, represent it with a “1”. For example the equation 2 H2O  → 2 H2+O2 would be represented as 2,2,1. ____As2S3 + ____O2 

Use the equations below to solve the following gas law problem.  P1V1T2 = P2V2T1                          1 atm = 760 mm Hg = 760 torr A sample of gas collected at 21.0°C and 0.868 atm, has a volume of 1.83 liters.  What volume will the gas occupy if the temperature is increased to 38.0°C and the pressure is reduced to 0.658 atm? To receive full credit:  You must use the math equation editor in the tool bar to insert the final gas law equation (with numbers and units) that you used to solve the problem.  Be sure to include the answer. Or, show your work on a separate sheet of paper and submit in the Unit 2 Exam pictures dropbox after completing the Exam. 

Assign oxidation numbers to each element in the following reaction. Write the oxidation number of the individual element in the box beside the element.  In the case of the compounds, write the oxidation number of the first element in the first box and the oxidation number of the second element in the second box. Then identify the element oxidized and the reducing agent.  I-1 [I] + (MnO4)-1 [Mn],[O]   I2 [I2]  +  MnO2 [Mn2],[O2] What is the element oxidized? [elementoxidized] What is the reducing agent? [reducingagent]

Use the equations below to solve the following gas law problem.  P1V1T2 = P2V2T1                          1 atm = 760 mm Hg = 760 torr A sample of gas collected at 21.0°C and 0.868 atm, has a volume of 1.83 liters.  What volume will the gas occupy if the temperature is increased to 38.0°C and the pressure is reduced to 0.658 atm? To receive full credit:  You must use the math equation editor in the tool bar to insert the final gas law equation (with numbers and units) that you used to solve the problem.  Be sure to include the answer. Or, show your work on a separate sheet of paper and submit in the Unit 2 Exam pictures dropbox after completing the Exam.