1) "The Avogadro constant (symbols: L, NA), also called Avogadro's number, is the number of "elementary entities" (usually atoms or molecules) in one mole, that is (from the definition of the mole) the number of atoms in exactly 12 grams of carbon-12.[1][2] The 2006 CODATA recommended value is 6.02214179(30)×10^23 entities per mole." "The Avogadro constant can be applied to any substance. It corresponds to the number of atoms or molecules needed to make up a mass equal to the substance's atomic or molecular mass, in grams. For example, the atomic mass of iron is 55.847 g/mol, so NA iron atoms (i.e. one mole of iron atoms) have a mass of 55.847 g. Conversely, 55.847 g of iron contains NA iron atoms. " Source and further information: http://en.wikipedia.org/wiki/Avogadro_constant 2) In the case of Titanium: "Standard atomic weight 47.867(1) g·mol−1" Source and further information: http://en.wikipedia.org/wiki/Titanium From above, we know that 47.867  g of Titanium contains NA Titanium atoms. 3) So we just yet need to calculate the mass of the Titanium cube. Edge length in SI units: 2.64 in = 2.64 * 25.4 * 10−3 m Volume of the cube: (2.64 * 25.4 * 10−3 m)³ Mass of the cube: M = (2.64 * 25.4 * 10−3 m)³ * (4.50 * 10^-2 kg / 10^-6 m³) = 301517 * 10^-3 * 4.50 * 10^-2 kg = 13.568 kg Number of Titanium atoms in the cube: (13.568 / 55.847 * 10^-3)* 6.02214179 * 10^23 = 1,468 * 10^23

Correction: Mass of the cube: M = (2.64 * 25.4 * 10−3 m)³ * (4.50 * 10^-3 kg / 10^-6 m³) = 301517 * 10^-3 * 4.50 * 10^-3 kg = 1.3568 kg Number of Titanium atoms in the cube: (1.3568 / 55.847 * 10^-3)* 6.02214179 * 10^23 = 1,463 * 10^22 = 1.463 * 10^19