Which is true of the enthalpy of a reaction?
A. Its value depends on which reactions are added
B. Its value is the same as the enthalpy of each intermediate reaction
c. Its value is always a negative kJ/mol
D. Its value does not depend on which reactions are added

Answers

Answer 1

D. It’s value does not depend on which reactions are added


Related Questions

Which sequence of steps describes the life cycle of a lake?
A. Runoff fills a depression - sediments build up - water becomes
increasingly shallow
B. Runoff fills a depression - sediments are eroded - water becomes deeper
C. Runoff fills a depression - sediments build up
- water rises continuously
D. Runoff fills a depression - sediments are eroded - water spreads over a wider area

Answers

Answer:

The actual sequence of steps which describe the life cycle of a lake is given below:

C. Runoff fills a depression - sediments build up

- water rises continuously

Explanation:

This is because, the water which builds up as a result of the runoff water accumulating on the depression helps towards building up. When it must have accumulated greatly, it ends up forming a lake.

Given the structural formula: This compound is classified as an

Answers

Answer:

A.) aldehyde is the answer

From the given structural formula, the compound is ethanamide and thus, belongs to the group of amides. Thus, the correct option is B.

Amide is a functional group of organic compounds having an acyl group (R-C=O) linked to amine group (-NR¹R² where R¹ and R² are hydrogen atoms or alkyl groups). The amide functional group is given as -CON= (not double bond with N, but two distinct single bonds).

Amides can be classified into the following types depending on the moiety attached to nitrogen other than the carbonyl carbon:

1. Primary amides - amide in which the nitrogen atoms is attached to two hydrogen atoms

2. Secondary amides - in which the nitrogen atom is attached to one hydrogen and one alkyl group.

3. Tertiary amides - in which the nitrogen atom is attached to two alkyl groups.

Learn more about amides in:

https://brainly.com/question/29595493

#SPJ2

Determine when to put on disposable gloves for work in the lab. Select one: After cleaning all the glassware for the experiment Before entering the laboratory room After setting up all the glassware but before handling chemicals Before handling any glassware or chemicals for the experiment

Answers

Answer: Disposable gloves should be put on before handling any glassware or chemicals for the experiment for work in the lab.

Explanation:

Disposable gloves are helpful in protecting skin of a person from coming in direct contact with chemicals.

As a result, it is important to wear disposable gloves before handling any glassware or chemicals for carrying out an experiment.

Thus, we can conclude that disposable gloves should be put on before handling any glassware or chemicals for the experiment for work in the lab.

Please help, only a couple of days left!!!

Answers

Answer:

the heat from the universe during the big bang

a.k.a.

ITS A

Explanation:

the universe is still expanding, so what is gonna be used to create that new matter that's expanding the universe? energy and heat from the beginning of the universe! the universe started off as this point that was probably smaller than a quantum foam and infinite heat and started expanding from there

Bit bang has to do it with ut

When your body is warmed by the sun during the winter, this process is said to be

a. exothermic.
b. endothermic.
c. isothermic.
d. none of the above

Answers

Answer:

B. Endothermic

Explanation:

Your body is absorbing the heat.

If 15.0 mL of phosphoric acid completely neutralizes 38.5 mL of 0.150 mol/L calcium hydroxide, what is the concentration of the phosphoric acid?

Answers

Answer:

Let me give it a try.

H3PO4 + Ca(OH)2 = Ca3(PO4)2 + H2O

Balancing this reaction

2H3PO4 + 3Ca(OH)2 == Ca3(PO4)2 + 6H2O.

Moles= Molarity x Volume

Volume = 38.5ml = 0.0385L

Moles of Ca hydroxide = 0.150m/L x 0.0385L

(Notice the units canceling out...leaving moles).

=0.005775moles of Ca(OH)2.

From balanced reaction...

3moles of Ca(OH)2 completely reacts with 2moles of H3PO4

0.005775moles of Ca(OH)2 would completely react with....

= 0.005775 x 2/(3)

=0.00385moles of H3PO4.

Now we're looking for its Concentration in Mol/L

Molarity=Moles of solute/Volume of solution(in L)

Volume of solution assuming no other additions to the reaction = 15ml + 38.5ml =53.5ml =0.0535L

Molarity = 0.00385/0.0535

=0.072Mol/L.

If this is wrong

then Simply Try The formula for Mixing of solutions

C1V1 = C2V2

0.15 x 38.5 = C2 x (15+38.5)

C2 = 0.11M/L.

A + 2 B + 4 C → products is known to be second order in A, first order in B and independent of the concentration of C. What is the value of the rate constant for this reaction if its rate is 0.783 M · s−1 when [A] = 5.00 M, [B] = 7.00 M, and [C] = 3.00 M? −2 −1 Answerinunitsof M ·s .

Answers

Answer:

4.47 × 10⁻³ M⁻² s⁻¹

Explanation:

Let's consider the following generic equation.

A + 2 B + 4 C → products

This reaction is known to be second order in A, first order in B and independent of the concentration of C (zero order in C). The rate law is:

rate = k × [A]² × [B] × [C]⁰

rate = k × [A]² × [B]

where k is the rate constant

When the rate is 0.783 M/s, [A] = 5.00 M, [B] = 7.00 M, and [C] = 3.00 M, the rate constant is:

k = rate / [A]² × [B]

k = 0.783 M/s / (5.00)² × (7.00) = 4.47 × 10⁻³ M⁻² s⁻¹

how could an environmentally sustainable biofuel production be ensured in biofuel
production​

Answers

Answer:

Explanation:

4.6 How could an environmentally sustainable biofuel production be ensured? ... Perennial feedstock crops, such as grasses or trees, can diversify production systems and help improve marginal or degraded land. Domestic government policy must become better informed of the international consequences of biofuel development.

Find the surface area of a square pyramid with side length 5 cm and slant height 4 cm.

Answers

Answer:

h = height

s = slant height

a = side length

P = perimeter of base

e = lateral edge length

r = a/2

V = volume

L = lateral surface area

B = base surface area

A = total surface area

Explanation:

Volume of a square pyramid:

V = (1/3)a2h

Slant Height of a square pyramid:

By the pythagorean theorem we know that

s2 = r2 + h2

since r = a/2

s2 = (1/4)a2 + h2, and

s = √(h2 + (1/4)a2)

This is also the height of a triangle side

Lateral Surface Area of a square pyramid (4 isosceles triangles):

For the isosceles triangle Area = (1/2)Base x Height. Our base is side length a and for this calculation our height for the triangle is slant height s. With 4 sides we need to multiply by 4.

L = 4 x (1/2)as = 2as = 2a√(h2 + (1/4)a2)

Squaring the 2 to get it back inside the radical,

L = a√(a2 + 4h2)

Base Surface Area of a square pyramid (square):

B = a2

Total Surface Area of a square pyramid:

A = L + B = a2 + a√(a2 + 4h2))

A = a(a + √(a2 + 4h2))

Please help I’ll give brainliest

Answers

Answer:

N2, O2 and Br2

Explanation:

N2, O2 and Br2 are formed of two atoms, so they are diatomic

This is a list of the seven diatomic elements. The seven diatomic elements are:

Hydrogen (H2)

Nitrogen (N2)

Oxygen (O2)

Fluorine (F2)

Chlorine (Cl2)

Iodine (I2)

Bromine (Br2)

Tenisha solved the equation below by graphing a system of equations. help!!!!!

Answers

Answer:

(1.0, 1.4)

Explanation:

Graph the two equations [tex]\log_3 5x[/tex] and [tex]\log_5 (2x+8)[/tex]. The point of intersection is the solution to the system of equations.

Graph on Desmos:

[tex]\log_3 5x\implies \text{Red},\\\log_5 (2x+8)\implies \text{Blue}[/tex]

an engineer chooses to use bamboo as a building material because it grows quickly and needs little space to grow. This is an example of?

Answers

Mark Brainliest please

Answer: This is an example of Green Design

Green design can be described as a method in which any building project is made by minimizing the harmful effects of construction on humans and environment. Green design is a sustainable design which is better for the economy too. In a green design, eco- friendly materials are used for construction works.
In the scenario discussed in the question, an engineer is using bamboo as a building material due to its eco- friendly features. Hence, it is an example of green design.

Answer:

A) This is an example of Green Design

Explanation:

WHAT IS EXOTHERMIC EXPLAIN

please ।
।।।​

Answers

Answer:

Exothermic reactions are reactions or processes that release energy, usually in the form of heat or light. In an exothermic reaction, energy is released because the total energy of the products is less than the total energy of the reactants.

Explanation:

I hope this helps u have a nice day ☘

Answer:

An EXOTHERMIC reaction is when energy is released.

What is the pH of a solution?
O A. A measure of the strength of the acid
B. A measure of the buffering ability of the solution
O c. A measure of the hydrogen gas concentration
O D. A measure of the acidity of the solution

Answers

Answer:

D. A measure of the acidity of the solution

Explanation:

pH is a measure of how acidic or basic a solution is, and is measured on a scale from 0-14, where 7 is neutral, anything less than 7 is acidic, and anything more than 7 is basic.

What is the delta H when 72.0 grams H2O condenses at 100.00C?

Here are some constants that you MAY need.

specific heats heat of fusion heat of vaporization

H2O(s) = 2.1 J/g0C 6.01 kJ/mole 40.7 kJ/mole

H2O(L) = 4.18 J/g0C

H2O(g) = 1.7 J/g0C



2930 kJ


163 kJ


-163 kJ


-2930 kJ

Answers

Answer: The value of [tex]\Delta H[/tex] is -163 kJZ

Explanation:

The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)

We are given:

Given mass of water = 72.0 g

Molar mass of water = 18 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of water}=\frac{72.0g}{18g/mol}\\\\\text{Moles of water}=4mol[/tex]

Calculating the heat released for the condensation process:

[tex]\Delta H=n\times \Delta H_{(vap)}[/tex] ......(2)

where,

[tex]\Delta H[/tex] = amount of heat released

n = number of moles of water = 4 moles

[tex]\Delta H_{(vap)}[/tex] = specific heat of vaporization = -40.7 kJ/mol

Negative sign represents the amount of heat released.

Putting values in equation 2:

[tex]\Delta H=4mol\times (-40.7kJ/mol)=-163kJ[/tex]

Hence, the value of [tex]\Delta H[/tex] is -163 kJ

A. 2 pts: In terms of conservation of mass, what were the results of each experiment (which one conserved mass and which one did not)?
B. 4 pts: PROVIDE a SPECIFIC explanation for "why" the results in both videos were different.
. 2 pts: Discuss differences in the experimental steps between the two videos (for example what was done in video one that was not done in
video two, why would this make a difference in conserving mass?)
• 2 pts: Look at both chemical equations (below for convenience), what difference in the type of products would have contributed to the
differences in why one conserved mass and one did not?
REACTION 1: Pb(NO3)2 (aq) + 2K1 (aq) --> 2KNO3 (aq) +Pölz (s)
• REACTION 2: NaHCO3(s) + CH3COOH(aq) → CO2(g) + H2Om + CH3COONa(aq)

Answers

Answer:

dftdffdgxrdfdrdxxxxdddddddddddddeeertdffddy

What happens when an unstable nucleus undergoes radioactive decay?
A. Electrons change energy levels to balance the nucleus.
B. Energy is absorbed by the nucleus to make it more stable.
O C. Particles or electromagnetic radiation are emitted.
D. The nucleus increases in mass through radioactive decay.

Answers

i believe the answer is C. an unstable nucleus emits radiation and is transformed into the nucleus of one or more elements. i hope this helps!

Explain why solids and liquids are difficult to compress
whereas gases can easily be compressed.

Answers

Answer:

Because they take up a certain amount of volume because there is no space in-between the particles, a gases can be compressed because there is alot of space in-between each particle

Explanation:

Which of the following best describes a pair of elements that will form an ionic bond

Answers

Answer:

One of the elements must be a metal and another be a non metal.

One of the elements must lose electrons and the other must gain electrons.

1. In 1996 a meteor crashed into the Earth near Steelsville, Ontario. The resulting meteorite was found to contain 5,790 g of Molybdenum Chloride having a formula of Mo2Cl9. How many molecules of Mo2Cl9 are present in the 5,790 g meteor?

Answers

Answer:

6.38×10²¹ molecules

Explanation:

Formula for molybdenum chloride is:

Mo₂Cl₁₀

Molar mass is : (Molar mass for Mo) . 2 + (Molar mass for Cl) . 10

95.94  . 2 + 35.45  . 10 = 546.38 g/mol

We determine moles that are contained in 5.790 g of Mo₂Cl₁₀

5.790 g . 1 mol /546.38 g = 0.0106 moles

We count the molecules:  0.0106 mol . 6.02×10²³ molecules / mol =

6.38×10²¹ molecules

Remember that 6.02×10²³ is also called Avogadro's number (NA) which is the number of particles of anything, that are contained in 1 mol.

Which of the following could possibly be true about a strong acid? (Check all that apply:).
It will completely dissociate (break apart) when dissolved in water.
It could have a pH of 6
It could have a pH of 13
Only a few of the acid molecules will dissociate (break apart).
It could have a pH of 2.
It could have a pH of 9

Answers

Answer:

it could have a pH of 2 it will completely dissociate when dissolved in water

if five elements have atomic numbers 2,3,6,9 which two numbers are the most reactive??​

Answers

Explanation:

[tex]element \: with \: 2 \: atomic \: number \\ \\ is \: stable \: because \: it \: has \: already \: \\ \\ completed \: its \: orbit \: \\ \\ but \: atomic \: number \: with \: 3 \: and \: 9 \\ \\ will \: have \: to \: become \: stable \: \\ \\ after \: giving \: one \: electron \\ \\ so \: \: element \: with \: 3 \: and \: 9 \: atomic \: number \\ \\ is \: most \: reactive[/tex]

Which question would most likely be studied by a biologist?
A.
How can a drug that treats cancer be synthesized?
B.
How can cancer-causing substances be regulated?
C.
How much ultraviolet radiation passes through the atmosphere?
D.
What causes cancer cells to grow uncontrollably?

Answers

Answer:

The correct answer would be - D. What causes cancer cells to grow uncontrollably?

Explanation:

A Biologist is a person that studies living organisms and the study of living organisms and their process called biology. Biology is a very vast field that involves many branches such as zoology, botany, biochemistry, immunology, biophysics, anatomy, ecology and many more.

So, given all are can be an example of the study biology wanted to do, however, the question most likely studied by a biologist would be What causes cancer cells to grow uncontrollably as it deals with an organism and their biological process.

Joelle is a manager at a construction company, and she is interested in the chemistry behind the materials they use. She has begun studying the materials used to fill walls. She knows that to keep the temperature inside a room steady the material must be a thermal insulator, and she predicts that materials should not be acidic or else they would dissolve too easily in water.

Which of these is a molecular ingredient that could be used in a wall-filling material ?

C27H36N2O10
Na6Ba6
NeNa
HCl

Answers

Answer:

a

Explanation:

A molecular ingredient that could be used in a wall-filling material is C₂₇H₃₆N₂O₁₀, is not a good thermal insulator, hence option A is correct.

The big molecule C₂₇H₃₆N₂O₁₀ is a poor thermal insulator. Since NeNa is a relatively reactive chemical, it would probably dissolve in water far too quickly. The acidic molecule HCl would dissolve far too quickly in water.

Not a good thermal insulator is C₂₇H₃₆N₂O₁₀. It is a big molecule composed of a lot of hydrogen atoms. Since hydrogen atoms are excellent heat conductors, they would be ineffective in stopping heat from passing through a material used to fill a wall.

Thus, the option (A) C₂₇H₃₆N₂O₁₀ is correct.

Learn more about thermal insulator, here:

https://brainly.com/question/23134662

#SPJ6

Which defines the word planet?


A. A large body that revolves around the Moon.
B. A large body suitable for life.
C. A large body that contains water and land.
D. A large body that revolves around the Sun.

Answers

Answer:

I think it's D cause one of the requirements for a planet is that it has to revolve around a star

Which of the following best describes an electron transition?

A. An electron gains or loses energy and moves between continuous
energy levels.
B. An electron gains or loses charge and changes into a proton or a
neutron.
C. An electron gains or loses energy and moves between quantized
energy levels.
D. An atom gains or loses an electron and becomes an ion.

Answers

Answer:

A. An electron gains or loses energy and moves between continuous

energy levels.

Which of the following statements is correct about electrical insulators?
A. They do not contain any atoms.
B. Their protons are not allowed to move about freely.
C. The electrons are not able to move about freely.
D. They are good at conducting heat only.

Answers

Answer:

the answer is C in my opinion.. hope this might be helpful

What does a vacuole mean

Answers


a small cavity or space in tissue, especially in nervous tissue as the result of disease.

Answer:

a space or vesicle within the cytoplasm of a cell, enclosed by a membrane and typically containing fluid.

or

a small cavity or space in tissue, especially in nervous tissue as the result of disease.

Use mathematics to prove that the 5.50 grams of salicylic acid (C7H6O3) used in this experiment is equal to 0.04 mol.

Answers

Answer:

Please find the answer to the question below

Explanation:

In chemistry, the following mathematical formula is used to calculate the number of moles contained by a substance:

mole = mass of substance (g)/molar mass of substance (g/mol)

Molar mass of salicylic acid (C7H6O3) = 12(7) + 1(6) + 16(3)

= 84 + 6 + 48

= 138g/mol

Mass = 5.50grams

mole = 5.5/138

mole = 0.039

Approximately, the number of moles of 5.5grams of salicylic acid is 0.04moles. This is in accordance with the mole value (0.04) given in this question.

An example of a product made from a synthetic material is
Question 5 options:

A)

a PET plastic water bottle.

B)

knitted wool socks.

C)

a cotton t-shirt.

D)

a pine 2×4 board.

Answers

Hi there! A simple answer and explanation is below :)

Answer:

A) PET plastic water bottle

Explanation:

Plastic goes through a manufacturing process before being used to make bottles for liquids like milk, soda, motor oil, and shampoo, as well as dry items like pharmaceuticals and nutritional supplements. Plastic is made up of a variety of organic polymers, including polyethylene and ethylene, in its unprocessed condition. In a soft state, plastic can be molded into the desired shape and then cast into a solid stat

Other Questions
BRAINILEST PLZZZZZzzzzz Solve using the quadratic formula2x^2+x+67=0 Which sentence contains a linking verb ? What is the approximate measure of the leg opposite of angle A??? Morning donuts recently sold 14 donuts, of which 7 we're cake donuts. Considering this data,how many of the next 6 donuts sold would you expect to be cake donuts Hhhelllllppp qqquuuiiiccckkk Which territories were acquired by the United States as a result of a treaty after the Spanish-American War? Determine whether the stochastic matrix P is regular. Then find the steady state matrix X of the Markov chain with matrix of transition probabilities P. P=0.22 0.20 0.650.62 0.60 0.150.16 0.20 0.20 You can use this formula to convert a temperature in Celsius (C) to Fahrenheit (F).F = 95C + 32Use the formula to covert 55C to Fahrenheit. The area of a circle is 4 ft. What is the circumference, in feet? Express your answer in terms of \pi. quadratic formula?2x^2-4x+2=0A. 1 B. -4C. 6D. -2E. 2 Which of the following statements best explains why people in Latin America first began to practice Christianity?A.Native American traders converted to receive better trade terms with Christian merchants.B.Christianity was introduced after independence, and the religion quickly spread.C.African slaves brought Christianity with them to the New World.D.Catholic missionaries often forced native peoples to convert during colonization. Nathalie is willing to apply for a car loan. She is 18 years old, still lives at home with her parents and has a part-time job during nights while attending college. In this scenario, a bank's loan officer is most likely to approve the loan in case that Group of answer choices Nathalie maintains a 3.5 GPA. Nathalie signs over her parents car as collateral. Nathalie provides a cosigner on her loan. Nathalie increases her student loan. Determine whether the triangles are congruent. Explain your reasoning .SAS (Side, Angle, Side) or ASA (Angle, Side, Angle) Fill in the blank. In the triangle below, x=__. Round your answer to two decimal places. Which one hurry A.82B.94C.121D.144 PLZ HELP 30 PTS ANSWER FAST AND I GIVE BRAINLIEST AND 5 STARS TO THE PEOPLE WHO DON'T GET BRAINLIEST!!!!!Mr. Jacobs is going to make a histogram of the test scores from the last math test he gave. He plans to first organize the data into a stem-and-leaf plot and then make the histogram from the stem-and-leaf plot. The test scores are listed below.79, 82, 65, 61, 94, 97, 84, 77, 89, 91, 90, 83, 99, 71, 68, 77, 87, 85Which of the following histograms represents this data? Which artist is from the Cubism period?O Pablo PicasoO Arthur HiitnerO Michel AngeloO Edgar Degas The statue pictured here is mixed media art as long as which of the following is true?A. the statue is entirely 3DB. the skirt on the statue is fabricC. the statue is created by a famous artistD. the museum includes similar statues in the exhibition which is the correct classification square root of 32?