[ladydark]

0.75 grams of biodiesel have burned to heat 20.0 mL of water at 20.0*C, what is the final temperature of the water? assume all of the energy from combustion goes to heating water.

[sinthreck]

You need to work out the energy released from burning the fuel. There is not enough information listed in the question to do that.

Then apply the conservation of energy to work out the final temperature of the water.

Energy = mass * (specific heat capacity of water) * (change in temperature)