A student scores 74 on a geography test and 243 on a mathematics test. The geography test has a mean of 80 and a standard deviation of 5. The mathematics test has a mean of 300 and a standard deviation of 38. If the data for both tests are normally distributed, determine the z-scores for both distributions and decide on which test the student scored better relative to the other students in each class? z-score for geography class = z-score for mathematics class = student performed better in class.

What is the mole fraction of ethanol, C2H5OH (MW=46.08), if 75.41 g of ethanol is added to 145.00 g of water?

What is the pH when 44.0 mL of 0.033 M NaOH is added to 38.0 mL of 0.035 M HNO3?

A piece of metal with a mass of 611 g is placed into a graduated cylinder that contains 25.1 mL of water, raising the water level to 56.7 mL.  What is the density of the metal?

Determine if the graph below may be misleading and if it is, then why is it misleading.  

The SI prefixes kilo and centi represent, respectively:

The equilibrium constant, Kc=48.35 for the reaction shown below. The enthalpy change for this reaction at 25°C is -25.6 kJ. 2 A + B 3C What is the correct value of K for the reaction shown below? 3/2 C A + 1/2 B

Calculate the percent by mass of potassium nitrate in a solution made from 45.0 g KNO3 and 295 mL of water.  The density of water is 0.997 g/mL.

A patient has a peripherally inserted central catheter (PICC) line inserted to continue IV antibiotic therapy at home. With proper care, how long can this type of venous access device remain in place?

Calculate the mass of FeS formed when 9.42 g of iron reacts with 8.50 g of sulfur according to the following reaction.             Fe(s) + S(s) → FeS(s)