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
Mnenie [13.5K]
2 years ago
15

Hess’s law

Chemistry
1 answer:
Delvig [45]2 years ago
8 0

From the statement of Hess' law, the enthalpy of the reaction A---> C is +90 kJ

<h3>What is Hess' law?</h3>

Hess' law of constant heat summation states that for a multistep reaction, the standard enthalpy of reaction is always constant and is independent of the pathway or intermediate routes taken.

From Hess' law, the enthalpy change for the reaction A ----> C is calculated as follows:

A---> C = A ---> B + B ---> C

ΔH of A---> C = 30 kJ + 60 kJ

ΔH = 90 kJ

Therefore, the enthalpy of the reaction A---> C is +90 kJ

The above reaction A---> C can be shown in the enthalpy diagram below:

A -------------------> C (ΔH = +90 kJ)

\ /

\ / (ΔH = +60 kJ)

(ΔH = +30 J) \ /

> B

Learn more about enthalpy and Hess law at: brainly.com/question/9328637

You might be interested in
Which factor causes chemical weathering​ it for science
VMariaS [17]

Answer:

acid or sunlight

Explanation:

7 0
3 years ago
Read 2 more answers
How do cells reproduce? ∵∵∵∵∵∵∵∵∵∵∵∵∵∵∵∵∵∵
lora16 [44]

Answer:

Cells divide to reproduce. There are two primary methods used, one for somatic cells, which compose the organism’s body, and one for reproductive cells, or gametes.

Scientists call the process of somatic cell division mitosis. Mitosis has six distinct steps in which the cell organizes and copies the DNA in the nucleus. Once copied, each new cell has its own copy of the DNA. The six steps of mitosis are prophase, prometaphase, metaphase, anaphase, telophase and cytokinesis. Some authorities consider the non-dividing portion of the cell’s lifecycle, known as interphase, to be one of seven steps involved in mitosis; however, interphase cells are not actively dividing.

Sex cells, such as sperm or eggs, must divide differently. Sex cells only possess one-half of the DNA that makes up a new animal. That way, when they combine, the resulting organism gets half of its DNA from its mother and half from its father. Because sex cells only want half of the DNA in each cell, they go through a different division process called meiosis. In meiosis, the cells split a second time, which yields four daughter cells rather than two as with mitosis; however, this provides each daughter cell with 23 chromosomes in contrast to the 46 chromosomes in somatic cells.

8 0
3 years ago
Based on the three formulas shown, use one of them to solve for the purple yellow and red box and explain how you did it.
zysi [14]

P = 11.133 atm (purple)

T = -236.733 °C(yellow)

n = 0.174 mol(red)

<h3>Further explanation  </h3>

Some of the laws regarding gas, can apply to ideal gas (volume expansion does not occur when the gas is heated),:  

  • Boyle's law at constant T, P = 1 / V  
  • Charles's law, at constant P, V = T  
  • Avogadro's law, at constant P and T, V = n  

So that the three laws can be combined into a single gas equation, the ideal gas equation  

In general, the gas equation can be written  

\large {\boxed {\bold {PV = nRT}}}

where  

P = pressure, atm  

V = volume, liter  

n = number of moles  

R = gas constant = 0.08206 L.atm / mol K  

T = temperature, Kelvin  

To choose the formula used, we refer to the data provided

Because the data provided are temperature, pressure, volume and moles, than we use the formula PV = nRT

  • Purple box

T= 10 +273.15 = 373.15 K

V=5.5 L

n=2 mol

\tt P=\dfrac{nRT}{V}\\\\P=\dfrac{2\times 0.08205\times 373.15}{5.5}\\\\P=11.133~atm

  • Yellow box

V=8.3 L

P=1.8 atm

n=5 mol

\tt T=\dfrac{PV}{nR}\\\\T=\dfrac{1.8\times 8.3}{5\times 0.08205}\\\\T=36.42~K=-236.733^oC

  • Red box

T = 12 + 273.15 = 285.15 K

V=3.4 L

P=1.2 atm

\tt n=\dfrac{PV}{RT}\\\\n=\dfrac{1.2\times 3.4}{0.08205\times 285.15}\\\\n=0.174~mol

3 0
3 years ago
What is the molarity of a 10 L solution containing 5.0 moles of solute?
Setler79 [48]
Molarity = Moles of solute/ L(liters) of solution

So let's plug in the information. 

5.0 moles/10L = 0.5 M


3 0
3 years ago
Read 2 more answers
What are 5 reasons to be grateful of your teachers for?
4vir4ik [10]

Answer:

5 reasons to be grateful of your teachers for is

-->They open our minds to new possibilities. ...

-->They work very hard for us. ...

-->They never give up on us. ...

-->They turn our weaknesses into strengths. ...

-->They are our best guides. ...

7 0
3 years ago
Read 2 more answers
Other questions:
  • Consider the following incomplete reaction. Mg + 2Y ---&gt; MgCl₂ + H₂ Choose the formula for the missing substance Y.
    9·1 answer
  • Line spectra from all regions of the electromagnetic spectrum, including the Paschen series of infrared lines for hydrogen, are
    12·1 answer
  • Which object reflects light with with the longest wave
    5·1 answer
  • If there were only three electron groups around an atom, how would they be arranged?
    15·1 answer
  • Sixty miles/hour is how many ft/sec
    15·1 answer
  • To measure the amount of nickel in some industrial waste fluid, an analytical chemist adds sodium hydroxide solution to a sample
    8·1 answer
  • _KOH + _H₂PO4 → _K₂PO4 + _H₂O​
    13·1 answer
  • For parts of the free-response question that require calculations, clearly show the method used and the steps involved in arrivi
    12·1 answer
  • Iron has two oxidation states +2 and + 3 there are two possible equations for the redox reaction
    7·1 answer
  • Which of the following will affect the vapor pressure of a pure molecular substance? Select all that apply.
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!