Question

Compared to a 10-mole sample of NaCl(s), a 10-mole sample of NaCl(l) has a different
(1) number of ions
(2) empirical formula
(3) gram-formula mass
(4) electrical conductivity

Answer 1

NaCl(s) has ions but they can't move, while those of NaCl(l) can be separated under the application of electricity. Therefore, (4) electrical conductivity is the correct one.
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