And to see exactly what your hash does contain, use Data::Dumper (or one of its descendants). (I'm passing Dumper a reference to the hash because it prints it in a more hash-like manner that way.)

abaugher@Aliantha ~$ cat doit
#!/usr/bin/perl
use Modern::Perl;

my @array = ( 'key', 'value' );
my %hash = @array;

say "The value of 'key' is '$hash{key}'";

use Data::Dumper;
print Dumper \%hash;

abaugher@Aliantha ~$ perl doit
The value of 'key' is 'value'
$VAR1 = {
          'key' => 'value'
        };
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