Question

1) Cite the difference between atomic mass and atomic weight. 2) Without consulting any figures or tables, determine whether each of the electron configurations given below is an inert gas, a halogen, an alkali metal, an alkaline earth metal, or a transition metal. Justify your choices. (a) 1s22s22p63523p63d7452 (d) 1s22s22p6352 (b) 1s22s22p63s23p6 (e) 1s22s22p63s23p63d2452 (C) 1s22s22p5 (1) 1s22s22p63523p6451 3) (a) What type(s) of bonding would be expected for each of the following materials; brass (a copper- zinc alloy), rubber, barium sulfide (Bas), solid xenon, bronze, nylon, and aluminum phosphide (AIP)? (b) Compute the percent ionic character of the interatomic bonds for the following compounds: Ti02, ZnTe, CsCI, InSb, and MgCl2. 4) If the atomic radius of aluminum is 0.143 nm, calculate the volume of its unit cell in cubic meters. 5) Calculate the radius of a vanadium atom, given that V has BCC crystal structure, a density of 5.96 g/cm^3, and an atomic weight of 50.9 g/mol. 6) A hypothetical alloy has an atomic weight of 184.4 g/mol, a density of 12.30 g/cm^3, and an atomic radius of 0.146 nm. Determine whether its crystal structure is FCC, BCC, or simple cubic. 7) Table lists point coordinated for atoms found in the FCC unit cell below that are labeled with the following numbers; 5, 8, and 14. Represent fractional indices as decimals. Coordinate indices Atom number

Answer 1

1)Atomic mass (m_a) is the mass of an atom. A single atom has a set number of protons and neutrons, so the mass is unequivocal (won't change) and is the sum of the number of protons and neutrons in the atom. Electrons contribute so little mass that they aren't counted.

Atomic weight is a weighted average of the mass of all the atoms of an element, based on the abundance of isotopes. The atomic weight can change because it depends on our understanding of how much of each isotope of an element exists.

Data giuen 50 no 5.96n NA : 6.022 Χ/023 UCAN anadaurn 3y 3 Av 2. n Av 3V3 orn uting For 64 P NA 13 64x594x022 Xo