Ask questions and get helpful answers.

What mass of liquid water a t room temperature (25°C) can be raised to its boiling point with the addition of 40.0 kJ of energy?

  1. 👍
  2. 👎
  3. 👁
  4. ℹ️
  5. 🚩
4 answers
  1. to get the heat released or absorbed,
    Q = mc(T2-T1)
    where
    m = mass of substance (units in g)
    c = specific heat capacity (units in J/g-K)
    T2 = final temperature
    T1 = initial temperature
    *note: units of temp doesn't matter if it's in degree Celsius or Kelvin, as long as T1 and T2 have the same units (since it's difference in temperature or delta,T)
    **note: if Q is (-), heat is released and if (+), heat is absorbed

    for water, c = 4.184 J/g-K
    substituting,
    40 * 10^3 = m*(4.184)*(100 - 25)
    40000/(4.184)(75) = m
    m = 127.47 g

    hope this helps~ :)

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩
  2. Jai why did you multiply 40 by 10^3

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩
  3. Converting it to joules

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩
  4. Since it is 40 kilojoules; the ratio for kilojoules to joules is 1 to 1000, in other words by multiplying 40 by 10^3 (.0001), it is the same as dividing by 1000 to convert the kilojoules to joules.

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩

Answer this Question

Related Questions

Still need help?

You can ask a new question or browse existing questions.