Hello and welcome to Just Answer. My name is ***** ***** I will be happy to assist you with your electrical question.
1) No, the receptacle is no longer safe and needs to be replaced.
2) Burnt marks indicate that arcing took place. Turn the circuit breaker
to the OFF position when replacing the receptacle and also perform a visual inspection of the wiring
inside the electrical box. Look for arcing flashes and/or burnt marks inside the box or any partial melting of the insulation
on the wires. The box wires need to be confirmed that no damage to them took place.
3) The wires that terminate to the receptacle need to terminate to the side screws and not into the back-stab insert holes as these are prone to come loose over time.
4) If the receptacle box contains any wire nut splices, make sure the wires are properly spliced and the plastic wire nut is tightened.
Hope this helps………If you have any additional questions, let me know and I’ll be glad to answer them for you.
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