what could cause the engine to 'explode''?

What is your question?

Don't know jack about cars so please bare with me, also not positive on the engine being DOHC or SOHC 92k miles and recently put in oil and coolant temp gauge not even to half way point. I was driving on the HWY up a slight hill and noticed a major clanking/scrapping sound from the steering wheel and gas pedal area and it wasn't really wanting to accelerate as well as getting stuck on the rpm gauge. Quickly pulled over turned the car off and looked at it, everything seemed fine. I started it, and almost immediately didn't want to accelerate the gas pedal and steering wheel where shaking. It sounded like the bottom of the car fell out, then white smoke from the front and back with a trail of either water, oil or coolant possibly all, the smoke was very sweet smelling and the some of the mystery liquid was brownie red. Turned the car off and called a tow truck, the guy said my engine exploded, there is a huge chunk of metal just chilling by the engine. i have pictures, my question is what happened? and why? also is it repairable or just need a new car?