A geo student places and irregularly shaped rock with a mass of 28.63 in a standard cylinder containing 13.31 ml of water. If the water increases to 19.73 ml what is the density of the rock in g/cm^3

Molecular distances are usually given in nanometers (1 nm = 1 109 m) or in picometers (1 pm = 1 1012 m). However, the angstrom () unit is sometimes used, where 1 = 1 1010 m. (The angstrom unit is not an SI unit.) If the distances between the Pt atom and the N atom in the cancer chemotherapy drug cisplatin is 1.97 , What is this distances in nanometers? In picometers?

On October 21, 1982, the Bureau of the Mint changed the composition of pennies (see Exercise 120). Instead of an alloy of 95% Cu and 5% Zn by mass, a core of 99.2% Zn and 0.8% Cu with a thin shell of copper was adopted. The overall composition of the new penny was 97.6% Zn and 2.4% Cu by mass. Does this account for the difference in mass among die pennies in Exercise 120? Assume the volume of the individual metals that make up each penny can be added together to give the overall volume of the penny, and assume each penny is the same size. (Density of Cu = 8.96 g/cm3; density of Zn = 7.14 g/cm3).

To determine the density of atmospheric nitrogen. Lord Rayleigh removed the oxygen, water, and carbon dioxide from air, then filled an evacuated glass globe with the remaining gas. He determined that a mass of 0.20389 g of nitrogen has a density of 1.25718 g/L under standard conditions of temperature and pressure. What is the volume of the globe (in cm3)?