How much heat is required to raise a 50.0 g piece of iron from 25 °C to its melting point of 1538 °C? The specific heat capacity for iron is 0.451 J/g•°C. (a) 34.1 kJ (b) 168 kJ (c) 12.1 kJ (d) 6.78 kJ

Video transcript

Hey everyone. So here it says we have a 25 g sample of iron um and it's initially a 25°C. Here, we need to calculate the final temperature of the sample absorbs three killer joules of heat. Alright so here they give us mass which is m They give us heat which is Q. They give us initial temperature and they're asking for a final temperature together. This gives me the equation. Q equals M. Cap. Here. If we look up and we're gonna plug in 25 g first. If you look up the specific heat capacity of iron, you'll see that it is approximately .450 jewels over g times degrees C. Because specific heat capacity uses jules. I need to convert my heat also to jules. So three killer jules is equal to 3000 jewels. Now final temperature is changing temperatures really. Final temperature minus initial temperature. We're looking for a final so we don't know it. The initial is 25°C. Alright, so grams cancel out. Mhm. I'm going to first multiply these two together. So 3000 jewels equals 11.25 jules over degrees Celsius times T f minus 25 degrees Celsius, Divide both sides by 11. jules cancel out. And I'll have my portion and degrees Celsius which comes out to 266.67 degrees Celsius equals T. Final minus 25 degrees Celsius mm hmm Add 25°C to both sides. Mhm. So t final equals to 91.67°C. So this will represent the final temperature of my iron sample.