Chapter 3, Problem 86QAP

Answer the questions below, using LT (for is less than), GT (for is greater than), EQ (for is equal to), or MI (for more information required) in the blanks provided.

(a) The mass (to three significant figures) of $6.022\times {10}^{23}$atoms of Na 23.0 g.

(b) Boron has two isotopes, B-10 (10.01 amu) and B-11 (11.01 amu). The abundance of B-10 the abundance of B-11.

(c) If S-32 were assigned as the standard for expressing relative atomic masses and assigned an atomic mass of 10.00 amu, the atomic mass for H would be 1.00 amu.

(d) When phosphine gas, PH₃, is burned in oxygen, tetraphosphorus decaoxide and steam are formed. In the balanced equation (using smallest whole-number coefficients) for the reaction, the sum of the coefficients on the reactant side is 7.

(e) The mass (in grams) of one mole of bromine molecules is 79.90.