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(WCSP24) When 5.0 g of CaCl2 is dissolved in 25 g of solution, the temperature of the solution increases by 25  ̊C.  Select all of the statements that are true of this process.  

16. Carbon monoxide is a toxic gas.  The upper limit of carbon monoxide (CO) in air is 9 ppm (9.0 x 10-6) over an 8-hour period.  a. At this concentration, how many moles of CO are there in a bedroom with a volume of 29,000 L at 25 oC and 0.98 atm? (3 points, WCSP[x]) b. How many molecules of CO are in the room? (3 points, WCSP[x])   Enter the value from part a in the box below.   

10.  (WCSP24.[x]) Hot air is less dense than cold air and this is the reason that hot air balloons float! A hot air balloon on a cool summer morning is filled with air to a volume of 2.20 x 106 L and warmed to 195 °F (90 °C).  A hot air balloon must be inflated to a volume of approximately 2.60 x 106  L in order to float in air. a. (4 points) At constant pressure, provide a molecular-level explanation of the relationship between temperature and volume of a gas.   b.  (6 points) Calculate the temperature the gas must be (in °C) in order to float.   Enter the temperature below

 (WCSP24) Select the intermolecular force(s) that are present in: CH3CH2OH

8. (WCSP24.[x]) Heavy metals, such as calcium, can be extracted from water by a precipitation reaction.   Hard water has a Ca2+ ion concentration around 4.24 x 10-3 M.   When hard water is mixed with a solution of soda ash (sodium carbonate, Na2CO3), the calcium ions react to form a precipitate and the water is now “softened.”  The precipitate can be removed by filtration. a.  (8 points) Write the complete balanced equation and the net ionic equation that occurs when Ca2+ and sodium carbonate react. Circle the precipitate. b.  (6 points) A 1000 mL soda ash solution was prepared with 5.0 g of sodium carbonate (MW = 106 g/mol).  Calculate the concentration (in M) of the sodium carbonate in the solution.  Calculate the concentration of sodium ions Enter the concentration of sodium ions below.

Suppose we add the following variations to the edges. In which cases is the MST of the original graph still a MST of the updated graph?

You attended the delivery of monochorionic twins who were born at 33 weeks gestation.  One of the twins appeared much paler than then other twin in the delivery and so you ordered CBCs on both of them. Twin A had a hemoglobin level of 19.5 and twin B had a hemoglobin level of 10.2 with a retic count of 5%. Your diagnosis is:

An infant who is born with a birth weight of 4200grams is classified as _______.

Which of the following pregnant women is at highest risk for having an infant with congenital anomalies? 

Which of the following is the BEST definition of a bit?