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
IrinaVladis [17]
3 years ago
15

We can also use the equation for enthalpy change for physical phase changes. Consider the phase change H2O(l) → H2O(g). Calculat

e ΔHrxn.
Use ΔHf values from the table above.

ΔHrxn = _____
Chemistry
2 answers:
DIA [1.3K]3 years ago
7 0
Standard molar enthalpy:
H2O ( liquid water ) : - 285.8 KJ/mole
H2O ( water vapor ) : - 241.8 KJ / mole.
ΔHrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0
Answer: B ) 44.0 KJ  
VLD [36.1K]3 years ago
6 0

Answer: The value of enthalpy of the given reaction is 44.000 kJ/mol , that is energy is supplied to water to change into water vapors

Explanation:

H_2O(l)\rightarrow H_2O(g),\Delta H_{rxn}=?

Enthalpy of formation of water in liquid state,\Delta H_{f,H_2O(l)}=-285.820 kJ/mol

Enthalpy of formation of water in gaseous state,\Delta H_{f,H_2O(g)}=-241.820 kJ/mol

\Delta H_{rxn}=\sum \Delta H_f \text{of products}-\sum \Delta H_f \text{of reactants}

\Delta H_{rxn}=(-241.820 kJ/mol)-(-285.820 kJ/mol)=44.000 kJ/mol

The value of enthalpy of the given reaction is 44.000 kJ/mol, that is energy is supplied to water to change into water vapors.

You might be interested in
Give the formulas for the following
zubka84 [21]

Li2O

Fe(NO3)3

Al2O3

CuCl2

ZnSO4

All you have to do here is make sure your charges are balanced when you write the compound. For example, Iron (III) has a +3 charge, and nitrate has a -1 charge. You need 3 nitrates to match that charge, hence Fe(NO3)3.

8 0
3 years ago
The barium isotope 133ba has a half-life of 10.5 years. a sample begins with 1.1×1010 133ba atoms. how many are left after (a) 5
Sladkaya [172]
<span>a) 7.9x10^9 b) 1.5x10^9 c) 3.9x10^4 To determine what percentage of an isotope remains after a given length of time, you can use the formula p = 2^(-x) where p = percentage remaining x = number of half lives expired. The number of half lives expired is simply x = t/h where x = number of half lives expired t = time spent h = length of half life. So the overall formula becomes p = 2^(-t/h) And since we're starting with 1.1x10^10 atoms, we can simply multiply that by the percentage. So, the answers rounding to 2 significant figures are: a) 1.1x10^10 * 2^(-5/10.5) = 1.1x10^10 * 0.718873349 = 7.9x10^9 b) 1.1x10^10 * 2^(-30/10.5) = 1.1x10^10 * 0.138011189 = 1.5x10^9 c) 1.1x10^10 * 2^(-190/10.5) = 1.1x10^10 * 3.57101x10^-6 = 3.9x10^4</span>
4 0
3 years ago
Read 2 more answers
What are some of the body external defenses
tekilochka [14]
<span>these include your skin, tears, mucus, cilia, stomach acid, urine flow, 'friendly' bacteria and white blood cells called neutrophils.</span>
4 0
3 years ago
H2(g) + F2(g) → 2 HF(g) ΔH=-546 kJ
Arisa [49]

Answer: help please !!

Explanation:

4 0
3 years ago
Read 2 more answers
Find the equation of the line passing through the points (2, 1) and (5, 10).​
Vedmedyk [2.9K]

The equation : y=3x-5

<h3>Further explanation </h3>

Straight-line equations are mathematical equations that are described in the plane of cartesian coordinates

General formula

y-y1 = m(x-x1)

or

y = mx + c

Where

m = straight-line gradient which is the slope of the line

x1, y1 = the Cartesian coordinate that is crossed by the line

c = constant

The formula for a gradient (m) between 2 points in a line

m = Δy / Δx

  • Gradient

\tt \dfrac{10-1}{5-2}=3

  • Equation

\tt y-1=3(x-2)\\\\y-1=3x-6\\\\y=3x-5

3 0
2 years ago
Other questions:
  • Draw aspartic acid (aspartate) at ph 1, ph 7, and ph 13. include hydrogen atoms.
    13·2 answers
  • Which substances will make a salt when combined? Vinegar and antacids Soda and wine Soap and ammonia Fertilizer and detergent
    7·2 answers
  • Why do you cool down tea extract in ice to below 40°c before adding dichloromethane?
    8·1 answer
  • what does the law of conservation of energy state? explain.please help quickly:(((( ill give u brainliest please!!
    8·1 answer
  • Cells perform many functions in living organisms. Which of the following processes occur in cells? A. extracting energy B. excre
    9·2 answers
  • Is cooking oil polar or non polar
    8·1 answer
  • *WILL GIVE BRAINLIEST TO CORRECT ANSWER *<br> **QUESTION IS IN PICTURE**
    8·2 answers
  • How many grams in 4.5 moles of H2O?
    7·1 answer
  • 4. Methane, CH4, is one carbon atom bonded to four hydrogen atoms. In order to show
    7·1 answer
  • As the rate of physical weathering increases, the amount of chemical weathering also increases because
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!