It varies depending on the laptop model. Some are soldered in with a BGA socket. You have a chip with a PGA socket, so it isn't soldered in.
There are other concerns though, you will have to check with the laptop manufacturer to make sure that motherboard will support any of the i7 mobile CPUs, if the motherboard BIOS doesn't support them, you can't upgrade. There will also likely be thermal issues if you upgrade. The laptop manufacturer designed their cooling to cool a low powered dual core chip, the Pentium B970. You want to install a higher powered quad core CPU, which will generate much more heat, odds are even if you successfully upgrade your CPU, you are likely to run into overheating issues.