The Calamity - 101:11 It is a fiery fire!
In the context of verses 8, 9...11; Those whose scales are light; Those who deny the signs and miracles:
The Heights/7:8 On that Day the scales will be true. Those whose scales are heavy are those who have succeeded.
The Heights/7:9 And those whose scales are light are those who have lost their character by being unjust against Our signs.

The Prophets/21:47 We will set up scales of justice for the Day of Resurrection. No injustice will be done to anyone. We will take into account even the weight of a grain of mustard seed. We are sufficient as the reckoners.

The Believers/23:103 As for those whose scales are light, they are the ones who will abide in Hell forever because they have caused themselves loss.
The Believers/23:104 The Fire will lick their faces while they are miserable therein.
The Believers/23:105 Were My Verses not recited to you and did you not deny them?

The Shaking/99:7 Whoever does a single atom´s weight of good deeds will see it.
The Shaking/99:8 And whoever does an atom´s weight of evil will see it.

The Calamity/101:5 And the mountains will be like discarded wool.