First time charging take long hours in SAMSUNG J7?

[Sajith Jayawardhana]

I have charged the J7 phone first time 9hrs and 30 mits still it was charged up to 73%.
It was charged Up to 50% with in one hour. Is it normal to take long hours to charge the battery fully for the 1st time?
It was 5% remaining when switched on the phone 1st time and then I switch off and plugged in?