1 a. The total amount of fresh water on earth is estimated to be 3.73 x 108 km3. What is this volume in cubic meters and in liters?
b. Explain the operation of a cathode-ray tube. Describe the deflection of cathode rays by electrically charged plates placed within the cathode-ray tube. What does this imply about cathode rays?
2.a There are four isotopes of strontium with mass numbers 84, 86, 87, 88.
1. Write the nuclide symbol for each of the atoms.
2. How are these isotopes alike?
3. How are they different?
4. Why is the atomic mass of strontium listed on the periodic table not a whole number?
b. Emerald-green crystals of the substance NiSO4.6H2O are used in nickel plating. What is the chemical name of this compound?
c. Complete the following table for Ag
Name of Element
Symbol
Atomic Number
Mass Number
Number of Protons
Number of Neutrons
Number of Electrons
Ag
3 a. Balance the following equation. Write the names of the reactants and products.
b. For the following chemical reaction, write the correct element and/or compound symbols, formulas, coefficient needed to produce a complete balanced equation. Reactants are elements and product(s) are binary compounds.
Na + S ------------------à
4. Illustrate the steps in the scientific method using Rosenberg's discovery of the anticancer activity of cisplatin.
5.a. 20.0 g marble is treated with 100.0 mL hydrochloric acid (density 1.096 g/mL). The marble dissolves, giving a solution and releasing carbon dioxide gas. The solution weighs 120.8 g. What is the mass of carbon dioxide given off during the reaction? The density of carbon dioxide gas is 1.798 g/L. How many liters of CO2 gas are released?
b. Ultrapure Si is used to make solid-state devices, such as computer chips. What is the mass in grams and pounds of a circular cylinder of silicon that is 12.50 cm long and has a radius = 4.50 cm?
Volume of Cylinder = π x radius2 x length.
Density of Si = 2.33 g/cm3