Texts:
1. At a certain temperature, NaCl has a solubility of 3.60 kg NaCl per 10.0 kg of water. How many pounds of NaCl can dissolve in 0.75 kg of water? Round your answer to two decimal places, but do not write the units.
2. A large piece of iron has a density of 7.87 g/mL. What is the density of a piece of iron that is two times heavier?
a. 7.87 g/mL
b. 15.74 g/mL
c. 3.94 g/mL
d. 0.254 g/mL
e. higher than 7.87 but not necessarily two times higher
3. When 50 grams of oil is mixed with 20 grams of water, a heterogeneous mixture forms, with the oil layer on top and the water on the bottom. Which choice best explains why the water is on the bottom?
a. The sample of water is heavier than the sample of oil.
b. Water has a higher density than oil.
c. The volume of water is larger than the volume of oil.
d. Water has a lower density than oil.
e. The sample of water has a lower mass than the sample of oil.
4. If an equal amount of energy is added to equal masses of each choice below, which ONE will have the smallest change in temperature?
a. Ar (Cs = 0.520 J g^(-1) ºC^(-1))
b. Be (Cs = 1.82 J g^(-1) ºC^(-1))
c. water (Cs = 4.184 J g^(-1) ºC^(-1))
d. ethanol (Cs = 2.44 J g^(-1) ºC^(-1))
e. all will have the same change in temperature
5. When 60.0 g of a dilute aqueous acid solution was mixed with 60.0 g of a dilute base solution, the temperature of the mixture increased from 24.1 °C to 29.3 °C. What is the heat of the reaction? Assume the specific heat of the solution (Cs = 4.184 J g^(-1) ºC^(-1)) and the heat capacity of the calorimeter = 84 J ºC^(-1). Round your answer to a whole number, but do not write the units.