I have attached all the problems, but really if you just do one so I understand how to do it, that would be great!
Perform the following heat calculations. You must show all work and include units on answers to receive full credit.

a. How much heat is required to raise the temperature of 10.0 g of iron from 25°C to 100.°C? The specific heat capacity of iron is 0.46 J/g°C.


b. The specific heat capacity of water is 4.184 J/g°C. How much heat is required to heat 500.0 g of water from 50.0°C to 100.°C?


c. A 45.4 g sample of lithium is cooled from 250.0°C to 25.0°C. The specific heat capacity of lithium is 3.56 J/g°C, what amount of heat is released?


d. How many kilojoules of heat are released when 0.72 mole of oxygen gas are used to combust methane?
CH4 (g) + 2O2 (g) → CO2 (g) + 2H2O (ℓ) + 890kJ


e. How much heat is released when 1.4 mol of hydrogen fluoride are produced?
H2 (g) + F2 (g) → 2HF (g) + 536kJ

Respuesta :

Answer:

Answer of question a is 345J.

Explanation:

In question a following is given in data:

-mass of iron (m) = 10.0 g

-temperature (ΔT) = final temperature- initial temperature= 100-25=  75 degree Celsius

-Specific Heat capacity of iron (c)= 0.46J/g°C.

Heat (Q)=?

Solution:

Formula for Heat is :

Q=m x c x ΔT

Q= 10 x 0.46 x 75

Q= 345 J.  

so, 345 joules of heat is needed to increase the temperature of 10 grams of iron.

  • From the above formula all other questions can easily be solved from the same procedure.