What is the difference between 3528 and 5050 LED strips?

MD 3528 has single chip packaged inside, and SMD5050 has three chips packaged inside.Usually,SMD5050 has the brightness which is three times than SMD3528.   

For example, each 3528 has  5-6 lumens, and each 5050 has 12-15 lumens. 

SMD3528: its dimension is 3.5mm * 2.8mm, power watts is 0.08W / Pcs 

SMD5050: its 5.0mm * 5.0mm, power watts is 0.24w/Pcs