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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?

Which of the following is a browser attack?

What is the binary equivalent of the hexadecimal number F2D4?

Which of the following represents the octal numbering system?

A _______ is simply a bundle of wires that carry signals and power between different components.