No need to store values in an intermediate array.

use strict;

my %new_hash_experiment = map {($_, undef)} qw(aa ab ac ad ae af);

foreach my $key (sort(keys(%new_hash_experiment)))
  {
    print "\nEnter a value for key: $key: ";
    chomp($new_hash_experiment{$key} = <STDIN>);
  }

foreach (sort keys %new_hash_experiment) 
  {
    print "$_ contains $new_hash_experiment{$_}\n";
  }
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