1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
disa [49]
3 years ago
9

How many kilojoules are released when 8.2 g of water condenses at 100 °c and cools to 15 °c?

Chemistry
1 answer:
MrRa [10]3 years ago
3 0

Answer:- 2.92 kJ of heat is released.

Solution:- We have water at 100 degree C and it's going to be cool to 15 degree C.

So, change in temperature, \Delta T = 15 - 100 = -85 degree C

mass of water, m = 8.2 g

specific heat of water, c = 4.184\frac{J}{^0C.g}

The equation used for solving this type of problems is:

q=mc\Delta T

Let's plug in the values in the equation and solve it for q which is the heat energy:

q = (8.2)(4.184)(-85)

q = -2916.248 J

They want answer in kJ. So, let's convert J to kJ and for this we divide by 1000.

q=-2916.248J(\frac{1kJ}{1000J})

q = -2.92 kJ

Negative sign indicates the heat is released. So, in the above process of coiling of water, 2.92 kJ of heat is released.

You might be interested in
How many moles are in 25 grams of dihydrogen monoxide
timurjin [86]
If you'd like the full working, here it is:

I calculated this by using the formula triangle.

Mass

Number Formula
Of moles Mass

To calculate the number if moles in a substance, you need to divide the Mass by the Formula mass. You get the formula mass by adding the atomic masses of the elements in the compound together. In this situation, H2O, it would be two hydrogen molecules plus one oxygen molecule which is 2 + 16. This is because the atomic mass of Hydrogen is 1 and the atomic mass of Oxygen is 16.

Now that we have the Formula mass we can go ahead and do the calculation since we already have the Mass. You do as follows:

Mass divided by Formula mass which is in this case - 25 divided by 18

By doing this calculation you will get the answer which is 1.38 moles which can be rounded to 1.4

Hope this helps :)
6 0
3 years ago
Read 2 more answers
Name the following compounds:
ankoles [38]
A) cesium chloride
B) barium oxide
C) potassium sulfide
D) beryllium chloride
E) hydrogen bromide
F) aluminum fluoride
3 0
3 years ago
Asap... define pure substances...​
gtnhenbr [62]

A pure substance refers to an element or a compound that has no component of another compound or element. Pure substances are made of only one type of atom or molecule. Hydrogen gas and pure iron are examples of pure substances. Hydrogen consists of hydrogen atoms only while iron consists of only iron atoms. Mixing two pure substances results in a mixture. To separate the two, scientists use a method known as filtration. Mixtures can either be homogeneous or heterogeneous. The measure used to determine how pure a substance may be called purity. Besides hydrogen and iron, other pure substances include gold, diamonds, sugar, and baking soda.

3 0
3 years ago
Read 2 more answers
Name the salts formed:
daser333 [38]

Answer:

1)magnesium nitrate +hydrogen

2)calcium chlorine+hydrogen

3)zinc sulfate +hydrogen

Explanation:

hope it helps

6 0
3 years ago
Can someone please help and list what each type of thing they are? (Element, Compound, Mixture of elements, Mixture of compounds
enot [183]
1. B
2. C
3. E
4. D
5. A
6. B
7. A
8. E
9. A

Hope this helps!
5 0
3 years ago
Other questions:
  • Jason has a balanced chemical equation and a rate law for a chemical reaction. What should he do to determine the overall order
    15·2 answers
  • Magma _____ to form igneous rock.
    5·1 answer
  • Water samples containing dissolved substances are called _____ solutions. A. solvent B. aqueous C. anhydrous D. elementary
    9·1 answer
  • 50.0 mL of an HNO^3 solution were titrated with 36.90 mL of a 0.100 M LiOH solution to reach the equivalence point. What is the
    13·1 answer
  • In step 2, of the experiment, the procedure uses 3.0M NaOH. However, the student notices that the only solution of NaOH is conce
    11·1 answer
  • The molecular weight of acetic acid is
    10·1 answer
  • I WILL GIVE A LOT OF EXTRA POINTS. PLEASE ANSWER ALL OF THEM ​
    7·2 answers
  • Por favor necesito enviar esto hoy
    13·1 answer
  • Let's repeat this process for the atoms that make up the substances that do not conduct when dissolved in water. What do you not
    9·1 answer
  • Convert 4.92 L of hydrogen at STP to moles.
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!