Difference between UA741 op am and LF356N
The 741 op-amp is an extremely old design based on bipolar transistors, dating back to 1968 (nearly 50 years ago!!). Due to its simplicity, it is commonly used for teaching purposes, but it has no place in modern circuits. Its characteristics are generally much worse than any modern op-amp.

The LF356 is a rather old part as well (from around 1978), but it's still newer than the 741. It uses a JFET input stage, and performs considerably better:


Bandwidth: LM741 = 1.5 MHz; LF356 = 5 MHz (3.3x better)
Slew rate: LM741 = 0.7 V/µS; LF356 = 7.5 V/µS (10x better)
Input impedance: LM741 = 2 MΩ, LF356 = 1012 Ω (6 orders of magnitude better)