Question 1
What is the structure of the "gray" allotropic form of tin that is used as a semiconductor?
◦ diamond-like
◦ simple cubic
◦ body centered
◦ graphite-like
Question 2
What statement is
not consistent with the chemistry of lead?
◦ It is used in making pipes, cables, paint pigments and electrodes for storage batteries.
◦ It has the highest density of the group 4A elements.
◦ It is commonly used as a fuel additive in gasoline to boost the octane rating.
◦ It is obtained from its ore galena (PbS) by roasting in air and then by reduction with carbon monoxide.