2. Atoms & Elements

In the complex ion [Fe(NH_3)_2Br_4]^{2-}, what is the oxidation state (charge) of the iron (Fe) atom? (Omit the + sign in your answer.)

How many grams of maltose (C12H22O11) are required to prepare 100 mL of a 15% w/v solution?

What mass (in mg) does 2.63 moles of nickel (Ni) have? (Atomic mass of Ni = 58.69 g/mol)

What is the mass, in grams, of 4.32 mol of GaI_3?

Which of the following is the correct molar mass of urea (NH2CONH2)?

What is the molar mass of sodium chloride (NaCl)?

Where would you look to find the molar mass of an element?

An alloy consists of 30 wt% Zn and 70 wt% Cu. What is the composition of the alloy in atom percent Zn?

What is the molar mass of Mg3(PO4)2?

A 38.0-g sample of the chlorofluorocarbon CF2Cl2 is analyzed. How many grams of chlorine (Cl) are present in the sample? (Atomic masses: C = 12.0 g/mol, F = 19.0 g/mol, Cl = 35.5 g/mol)