9. The following table lists some information
about certain elements in group 17.
ents
Element
Symbol
Atomic
Number
Melting
Point (°C)
Boiling
Point (°C)
9.
-233
-187
17
-102
-35
Izn
Br
I
35
-7.3
I
59
183
I
53
114
Which statement describes what happens
to these elements as atomic number
increases?
A. Both melting point and boiling point
decrease.
B. Melting point increases and boiling
point decreases.
C. Melting point decreases and boiling
point increases.
D. Both melting point and boiling point
increase.
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