HELPPPPPPPPPPPPPPPPPPPP
Answer:
See explanation
Explanation:
Turning on a flashlight: The chemical energy in the flashlight batteries is converted to electrical energy when the flashlight is turned on. The electrical energy is then converted to light (electromagnetic / radiant energy) and some thermal energy (little warmth from light in flashlight) by the light bulb. Chemical to Electrical to Light and Thermal
A Toaster: When electrical energy passes through the heating element in a toaster, it converts this electrical energy to thermal energy which helps to prepare toast. Electrical to thermal
Playing a violin: When the violin and the strings vibrate due to mechanical energy, it produces sound waves and sound energy. Mechanical to Sound
Nuclear power plant: Nuclear power plants use heat from fission to make steam that turns the turbine, creating mechanical energy. Mechanical energy turns the electric generator. Thermal to Mechanical
A gas tank has a volume of 28.1 m 3 and a pressure of 18.4 atm. The temperature of the gas is 32ºC. What is the Celsius temperature when the gas is put in an 11.2 m 3 tank with a pressure of 22.7 atm?
What is the atomic mass of Hafnium if in a sample, 10 have mass 176 amu, 38 have mass
177 amu, 54 have mass 178 amu, 28 have mass 179 amu, and 70 have mass 180 amu?
The atomic mass of Hafnium is 357.1amu and atomic mass is the total mass of the subatomic particles in an atom and is measured in atomic mass units
Here given data is if in a sample, 10 have mass 176 amu, 38 have mass 177 amu, 54 have mass 178 amu, 28 have mass 179 amu, and 70 have mass 180 amu then
The atomic mass is a weighted average of all of the isotopes of that element, in which the mass of each isotope is multiplied by the abundance of that particular isotope
We have to find average atomic mass = ?
Average atomic mass = atomic weight of Hafnium/100
Now we can substitute the known values
Then, Average atomic mass = (176×10)+(177×38)+(178×54)+(179×28)+(180×70)/100
Average atomic mass = 357.1amu
357.1amu is the atomic mass of Hafnium
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Best explanation and example will be mark BRAINLIEST.
State the octet rule.
Answer:
62,000,000 written in scientific notation is 6.2 × 107.
Explanation:
The smallest particle of an element that retains the properties of the element is called a(n)
.
Answer:
atom is smallest praticle of an element
Answer:
atom
Explanation:
Answer the questions please
The Newton's third law deals with action and reaction.
What is the Newton third law of motion?According to Isaac Newton, there are three laws that govern the motion of an object and this is the field that we call dynamics. They deal with the interaction of the force that acts on a body and causes it to move. Three laws of Isaac Newton deals with the various aspects of the motion of an object.
The Newton third law of motion states that action and reaction are equal and opposite. This implies that, when a force is exerted on a body, the body exerts the same magnitude of force back on the person that exerted the force but in this case, the force is acting in opposite direction.
A typical example of this law is when a gun is fired. It observed that as the bullet leaves the gun as the force acts on it, the gun has to recoil. The recoil of the gun owes to the reaction force.
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What is the average atomic mass of a sample of Calcium, if you have 37
atoms of Calcium-40 and 10 atoms of Calcium-41?
The calculated answer is 40x2/6.023x10²³
Calcium is a mineral that is most frequently linked to strong bones and teeth, but it also plays a critical role in blood clotting, assisting with muscular contraction, and regulating regular heartbeats and nerve activity. Calcium has a 40g molar mass (mass of 1 mole). I'm assuming that all you're looking for is the mass of two calcium atoms, which is incredibly little:
A mole of calcium weighs 40g and contains 6.023 x 10²³ atoms.
There would be 1.328x10-22 g of calcium if 2 calcium atoms have a mass of 40x2/6.023x10²³.
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which of these formulas could be only an empirical formula, only a molecular formula, either a molecular or an empirical formula? drag the appropriate items to their respective bins.
SO₂ represent molecular and empirical formula, B₄H₁₀ represent only molecular formula, CO represent molecular formula and empirical formula, C₄H₄O₂ represent only molecular formula.
What is Molecular Formula ?The chemical formula that gives total number of atoms of each element in one molecule of a compound is called Molecular Formula.
How to write the molecular formula ?First write the symbol of each element with its valency.Interchange the valencies with each other.Now, write the interchanged number and the formula.What is Empirical Formula ?Empirical formula is the formula of compound in which it exist in simplest whole number ratio of atoms present in a compound.
Thus from the above conclusion we can say that SO₂ represent molecular and empirical formula, B₄H₁₀ represent only molecular formula, CO represent molecular formula and empirical formula, C₄H₄O₂ represent only molecular formula.
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Disclaimer: The given question is incomplete on the portal. Here is the complete question.
Question: Consider the following four formulas: SO₂, B₄H₁₀, CO, C₄H₄O₂. Which of these formulas could be only an empirical formula, only a molecular formula, either a molecular or an empirical formula?
Need help asap, I completely forgot how to solve these
The correct scientific notation of the following numbers is as follows:
3.53 x [tex]10^{4}[/tex] cm9.21 x [tex]10^{4}[/tex] m8.4 x [tex]10^{-5}[/tex] km7 x [tex]10^{5}[/tex] ft9 x [tex]10^{3}[/tex] g9.03 kg2 x [tex]10^{1}[/tex] lbs5.6 x [tex]10^{-5}[/tex] amu2 x [tex]10^{-4}[/tex] m4.12 cm1.6 x [tex]10^{2}[/tex] N6.6 x [tex]10^{-1}[/tex] g5.3 x [tex]10^{5}[/tex] miles4.7 x [tex]10^{5}[/tex] days5 x [tex]10^{4}[/tex] ounces4.59 x [tex]10^{1}[/tex] g6.7 x [tex]10^{4}[/tex] m9.6 x [tex]10^{4}[/tex]8.78 x [tex]10^{3}[/tex] cm5.28 x [tex]10^{3}[/tex] cmExtremely big or small numbers can be presented using scientific notation to make them more intelligible. Although we are aware that whole numbers can never end, we are unable to put such massive sums of data on paper.Five guidelines for scientific notation:
The base must always be 10.The exponent must be an integer that is non-zero, meaning it may be positive or negative.The coefficient's absolute value is more than or equal to 1, but it must be less than 10.Both whole and decimal numbers, including positive and negative numbers, can be used as coefficients.The remaining significant digits of the number are carried by the mantissa.Learn more about scientific notation here:
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Which skill in the science process contains the units,number, and conversion?
The skill of Dimensional Analysis in the science deals with the conversion of units and numbers.
The physical quantities are only seven in basic. All the other quantities that we see are just derived quantities in one or the other.
While checking the correctness of a formula or while analyzing the reliability of an equation, we use dimensional analysis and convert the units into the dimension form.
Every fundamental quantity is given a Special notation like M for kg and L for meter.
Converting a bigger quantity into a smaller one is also a part of the dimensional analysis. As we know, we can measure the distance between our houses in meter but thing are different when it comes to astronomical distances.
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how did you know that the valency of chromium was going to be three in this situation of
hydrochloric acid + chromium hydrogen carbonate =
explain other cases as well-
Answer:
Explanation:
by checkng the chemical formula and oxidationn number
When mercury oxide is heated, it decomposes into mercury and oxygen. If 28. 4 g of mercury oxide decomposes, producing 2. 0 g of oxygen, what is the percent by mass of mercury in mercury oxide?.
The percent by mass of mercury in mercuric oxide is
93 %.
The formula of mercuric oxide is HgO. When mercury combines with oxygen, then mercuric oxide is formed.
The molecular mass of mercury oxide is 216 g/mol. Its melting point is 500°C.
The balance equation for the reaction of decomposition of mercury oxide is,
[tex]2HgO (s)→ 2Hg (l) + O _{2}(g)[/tex]
Mass of mercury oxide = 28.4 g
Mass of the oxygen = 2 g
The percent by mass of mercury in mercury oxide is,
[tex]Mass ℅= \frac{Mass \: of \: Mercury }{Mass \: of \: Mercury \: oxide} \times 100[/tex]
[tex] = \frac{28.4 - 2}{28.4} \times 100[/tex]
= 93 %
Therefore, the percent by mass of mercury in mercury oxide is 93 %.
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Help :/
can someone explain to me how you solve this
Use atom economy to argue which of these processes may be greener.
By the principle of atom economy the second process is more efficient.
What is atom economy?We know that the atom is the smallest particle of a substance that could take part in a chemical reaction. We are also aware that all compounds are composed of atoms and that a chemical reaction has to do with the rearrangement of atoms in such a way that be products could be formed.
In this case, we know that an organic product may be obtained in a sequence of reactions and the atom economy is very important in the nature of the process that is being carried out. Let us now take good look at the two processes that could be shown.
In the first process, we can see that there are a lot of products that could just be classified as side products and does not have a real relevance to the final products. In the second process, we have only one waste product and that is water.
As such, by the principle of atom economy the second process is more efficient.
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what mass of sodium azide is required to produce 2.6 ft (73.6 l) of nitrogen gas with a density of 1.25 g/l?
When a chemical element's density and volume are known, the mass of the chemical element can be calculated by multiplying the density and volume. When determining the mass of a chemical element, the link between the quantity of moles and molar mass is occasionally used.
Volume (V) of Nitrogen gas = 73.6 lDensity (ρ) of Nitrogen gas = 1.25 g/lMolar mass of N2 = 28g/molMolar mass of sodium azide (NaN3) = 65g/molMoles (n) of N2 = mass of N2 gas/molar mass= 73.6 * 1.25/28 = 3.29 moles
2NaN3→2Na+3N2, NaN3 is breaking into 2 moles of Na and 3 moles of NaN3.Using the above equation, no. of moles of NaN3 (N) = 2/3*n = 2/3*3.29 = 2.19 molesMass of sodium azide = N*molar mass = 2.19*65 = 142.35gTherefore, the mass of sodium azide is 142.35g.
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how do gas molecules move across a room
Answer: Diffusion
Explanation:
diffusion is when particles move from a region of higher concentration to lower concentration as a result of their random movement. They are in constant motion and the gas particles spread to fill the volume in the room.
Describe the
process of
sublimation
Sublimation is the conversion between the solid and the gaseous phases of matter, with no intermediate liquid stage.
Sublimation is that the method by that a substance changes from its solid to vaporous state while not transitioning to its liquid state. At a temperature and pressure below the substance's triple purpose, this method, Associate in Nursing heat-absorbing natural process, takes place.
Solids will directly elegant into the air if they need enough pressure level at a given temperature. Sublimation happens once a solid reaches its triple point below extreme pressure. The triple point is that the temperature and pressure at that a substance will at the same time exist all told 3 of its famed states of matter. A substance's triple point is one in every of its distinctive points.
The opposite of this method, during which a gas is remodeled straight into a solid state, is Desublimation or deposition.
The best illustration of sublimation is solid, that is Carbon dioxide that has been frozen. solid directly transforms from its solid state to a vaporous state, that is visible as fog, once it's exposed to air. The vaporous state of frozen dioxide is additional stable than the solid state.
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What is the initial source
of the energy you exhibit when you run?
Analyze the energy transformations that
occur during this process, from start to finish.
Express your analysis as a flow chart. Include
any details needed to explain the energy
transformations.
Running requires the body to transform potential energy into kinetic energy. A system's internal energy is known as its potential energy. When a system moves horizontally using kinetic energy, potential energy is consumed.
Potential energy is conserved as chemical energy in the human body. The food that a person eats during the day provides the chemical energy. The body requires a specific number of calories, or the energy from food, to carry out specific tasks. The runner will run out of potential energy and weary if they have not consumed enough calories during the day. This is due to the body's poor capacity for storing energy. Although energy cannot be created or destroyed, it may move. The majority of the person's stored energy is released as thermal energy while they run.
The impact of the runner's foot on the ground causes sound waves to be emitted, which releases energy from the runner's body. Every stride a runner takes releases energy from their body, thus it's critical for them to eat adequate chemical energy in the form of calories before their run. The body of the runner need a significant number of calories as a reserve so that they will have more energy to burn as their stored energy is released during the run.
The body is not particularly effective at preserving this energy when it uses the calories it has already consumed. The heat (thermal energy) that the body emits when it transforms its stored (potential) chemical energy into kinetic energy causes around 75% of the chemical energy that the runner has ingested to be wasted as the leg muscles contract to propel the runner forward. The flow chart is attached below.
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Question 1 (1 point)
How is atomic mass calculated?
O a
Ob
Oc
Od
Since the atomic mass is calculated as the sum of protons and neutrons, it is measured in amu. This is because protons and
neutrons each have a mass of 1 amu.
Since the atomic mass is calculated as the sum of neutrons, it is measured in amu. This is because neutrons have a mass of 1
amu.
Since the atomic mass is calculated as the sum of protons, it is measured in amu. This is because protons have a mass of 1
amu.
Since the atomic mass is calculated as the sum of protons and electrons, it is measured in amu. This is because protons and
electrons each have a mass of 1 amu.
Atomic mass calculated as the sum of protons and neutrons, it is measured in amu. This is because protons and neutrons each have a mass of 1 amu.
The sum of the masses of the protons, neutrons, and electrons in an atom or collection of atoms is known as the atomic mass. Since electrons are far lighter than protons or neutrons, the computation does not take their mass into account. A single atom's atomic mass is only its total mass, and it is usually given in atomic mass units, or amu.
Atomic mass = total number of protons present in the nucleus + total number of neutrons present in the nucleus of an atom
For elements having isotopes relative atomic masses are taken in consideration. The relative atomic mass is an average of the atomic masses of all the different isotopes.
Example- The atomic mass of carbon atom - with six neutrons and 6 protons the atomic mass is 12 amu.
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a sample of blood is found to contain 64.5 micrograms of valproic acid. how many milligrams of valproic acid does this blood sample contain?
The valproic acid contains 0.0645 milligrams
Conversion scale1000 microgram = 1 milligram
Data obatined from the questionFrom the question given, the following data were obtained:
Mass (in micrograms) = 64.5 microgramsMass (in milligrams) =?How to convert 64.5 micrograms to milligramsWe can convert 64.5 micrograms to milligrams as illustrated below:
1000 microgram = 1 milligram
Therefore,
64.5 micrograms = (64.5 micrograms × 1 milligram) / 1000 microgram
64.5 micrograms = 0.0645 milligrams
Thus, the valproic acid contains 0.0645 milligrams
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concentrated hydrochloric acid is 38.0% hci by mass, and it has a density of 1.189 g/ml at 20°c. the density of water at 20°c is 0.9982 g/ml.
739 ml volume of water would remain
Stepsvolume of solution = 1Litre = 1000 ml
density of solution = 1.189 g/ml
mass of solution = volume of solution × density of solution
= 1000 × 1.189 = 1189 g
conc of HCL is 38% by weight.
so, mass of HCL in 1189g of solution = 38% of 1189 = 451.82g
mass of H2O in solution = mass of solution - mass of HCl
= 1189g - 451.82g
= 737.18g
volume of H2O = mass of H2O/density of H2O
= 737.18/0.9982 ml
=739 ml volume of water would remain.
Hydrochloric acid A colourless to yellowish, smelly liquid, concentrated hydrochloric acid (36.5-38.0%) with a strong smell. Muriatic acid is another name for hydrochloric acid. Though extremely corrosive, it is not flammable. Benzene, alcohol, and water soluble. It is a serious skin and eye irritant, and breathing in the fumes can be dangerous.learn more about hydrochloric acid here
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the question you are looking for is
Concentrated hydrochloric acid is 38% HCl by mass, and it has a density of 1.189 g/ml at 20 celsius. The density of water at 20 celsius is 0.9982 g/ml. If all the HCl were somehow removed from 1.000 liters of this solution at 20 celsius, what volume of water would remain?
cogswell me, zhang z, carriquiry al, et al. sodium and potassium intakes among us adults: nhanes 2003-2008. am j clin nutr. 2012;96:647-657.
It has been observed that most US adult intake high levels of sodium and low level of potassium.
The American Health Association (AHA) published in its reports that US adults consume food containing more sodium and avoid food containing potassium. It causes various side effects and health-related problems. It was estimated that 99.4% of the total United States adults intake high levels of sodium on daily a basis. AHA guidelines recommend (<1500 mg) of sodium to be consumed. They consume even more than the Institute of Medicine's tolerable upper Intake level which is 2300 mg.
In the US, adults aged over 51 years or people suffering from diabetes, chronic kidney disease, or hypertension are recommended by the Dietary Guidelines to reduce sodium intake to 1500 mg per day. The overall result suggested that 98.8% consumed more than 1500 mg per day, and 60.4% consumed more than 3000 mg per day. These calculations of intake are more than double the recommendation guidelines. Only less than 2% of US adults and around 5% of US men consumed less than 4700 mg per day of potassium.
Therefore, it is concluded that the maximum US adult intake is high levels of sodium and low level of potassium.
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what is the concentration of hydroxide ion in an aqueous solution with an h concentration of 2 x 10-5 m?
The concentration of hydroxide ions is
4.89 x 10^-10
Given:
[H3O+] = 2 x 10^-5 m
To Find:
pOH of solution
Solution:
pH = -log[H3O+]
pH = -log[2 x 10^-5]
pH = 4.69
pH + pOH = 14
pOH = 14 - 4.69 = 9.31
Now , we can calculate the concentration of hydroxide ions of the solution very easily as shown below :
[OH-] = 10^-pOH
[OH-] = 10^-9.31
[OH-] = 4.89 x 10^-10
Thus , the concentration of hydroxide ions is
Thus , the concentration of hydroxide ions is 4.89 x 10^-10
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3 naoh(aq) c₆h₈o₇(aq) ⇌ na₃c₆h₅o₇(aq) 3 h₂o(l) step 3: calculate the volume of titrant required to reach the endpoint. calculate the volume in ml of a 0.200 m naoh solution needed to neutralize 345 ml of 0.0333 m c₆h₈o₇ standard solution.
Volume of NaOH solution needed to neutralize C₆H₈O₇ is 56.825 ml
In titration reaction , at equivalence point
Moles of Acid = Moles of Base
If [tex]M_1[/tex] is mole of acid and [tex]V_1[/tex] is volume of acid
[tex]M_2[/tex] is moles of base and [tex]V_2[/tex] is volume of base
Then [tex]M_1 V_1 = M_2 V_2[/tex]
Here in this question
[tex]M_1 = 0.200 M\\ M_2 = 0.0333 MV_1 = unknown\\V_2 = 345[/tex]
Therefore,
[tex].200 * V_1 = 0.033 * 345 ml[/tex]
[tex]V_1[/tex] = [tex]0.033 *345 / .200[/tex]
[tex]V_1 = 56.825 ml[/tex]
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the temperature of the mesosphere is much higher than the asthenosphere overall, but yet is is still a ductile solid. what keeps it from melting?
The temperature of the mesosphere is much higher than the asthenosphere overall, but yet is is still a ductile solid. The thing that keeps it from melting is high pressure.
What is the mesosphere?The mesosphere plays a crucial role in protecting the earth. Most meteors and asteroids are destroyed by the mesosphere before they can impact the earth's surface.
An area of the Earth's atmosphere is called the mesosphere. Directly above the stratosphere and beneath the thermosphere lies the mesosphere. It covers a distance of 31 to 53 miles, or 50 to 85 kilometers, above our planet. The mesosphere's temperature falls with height.
It should be noted that this high pressure that keeps it solid in form and does not let it melt down.
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The temperature of the mesosphere is much higher than the asthenosphere overall, but yet is is still a ductile solid. what keeps it from melting?
Cool temperature
Distance from the sun.
High pressure
Low pressure
Baking soda is also known as sodium hydrogen
carbonate. What is the mass of 1.00 mol of sodium hydrogen carbonate
(NaHCO.)?
the diameter of a hydrogen atom is about 1.05 cross times 10 to the power of negative 10 and exponent meters. a protein molecule has an overall length of 3000 times (or 3 cross times 10 cubed times) the diameter of a hydrogen atom.
Consequently, the protein molecule has a length of 315 x 10^-9 metres.
An atom of hydrogen contains what?Since it just has one proton and one electron, the hydrogen atom is the most basic of all atoms. The hydrogen atom can be found in three other isotopes: protium, deuterium, and tritium, in addition to this most prevalent form.The atomic number one of the lightest element is hydrogen, abbreviated H.How do you refer to an atom of hydrogen?Three isotopes of hydrogen are known. The isotopes of hydrogen have mass numbers of 1, 2, and 3, with mass 1 being the most prevalent. This isotope is also known as protium and is commonly referred to as hydrogen (symbol H, or 1H).
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choose the true statement(s) about ions. to be marked correct, you’ll need to select all true statements, as there may be more than one correct answer.
Cations have more protons than electrons, Anions result when atoms gain an electron.
What are electrons ?The electron, a subatomic particle, has a negative one elementary charge electric charge. The electron, a member of the first generation of the lepton particle family, is usually regarded as an elementary particle because it has no known components or substructure.
How electrons are in an atom ?A few straightforward rules can be used to calculate the quantity of protons, neutrons, and electrons present in an atom. The atomic number and the number of protons in the atom's nucleus are equal (Z). A neutral atom has the same number of protons and electrons as protons.
Around the nucleus, electrons are positioned in several shells. Only a fixed amount of electrons can fit in each subsequent shell. Filling begins with the innermost shell.
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2 2. blood alcohol content (bac) is sometimes reported in weight-volume percent and, when it is, a bac of 0.10% corresponds to 0.10 g of ethyl alcohol per 100 ml of blood. in many jurisdictions, a person is considered legally intoxicated if his or her bac is 0.10%. suppose that a 68 kg person has a total blood volume of 5.4 l and breaks down ethyl alcohol at a rate of 10.0 grams per hour. how many 145 ml glasses of wine, consumed over three hours, will produce a bac of 0.10% in this 68 kg person? assume the wine has a density of 1.01 g/ml and 11.5% ethyl alcohol by mass. glasses of wine 3. which of these molecules are polar? select all that apply. insert letters without spaces in the answer box, example abcd. a. ascl5 b. of2 c. socl2 d. brf4 e. ch2cl2 f. if4-
The quantity of 145 ml glasses of wine, consumed over three hours, will produce a bac of 0.10% in this 68 kg person is 2.3 glasses of wine.
What is the quantity?Quantity is the measurement of something that is present. It can be liquid, gas, or solid.
In three hours, to produce a BAC of 0,10% for a 68kg person (5,4L blood) you need to consume:
10 g of ethyl alcohol / 100 ml of blood x 5400 ml of blood + 10.0 g/h = 30.54g of ethyl alcohol
Assuming a 11,6% (v/v) of wine Where density of ethyl alcohol is 0,789 g/mL
30.54g of ethyl alcohol x 1ml ethanol / 0.789 x 100 ml wine/ 1.6 ml ethanol = 333.7 mL wine
333.7 mL wine / 145 ml = 2.3 glass of wine
Thus, the person needs to consume 2.3 glasses of wine.
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please answer question a and b please. i feel like they are wrong. thank you
rate is always positive; it is defined as the change in concentration of reactants or products over a period of time. the only time a negative sign is used is when expressing the change in concentration of a reactant over time, such as −δ[a]/δt for the reaction a→b.
For the rate of reaction a negative sign is used is when expressing the change in concentration of a reactant over time, such as −δ[a]/δt for the reaction A→B. Because the concentration of the reactant goes on decreasing with the time to form product.
What is Rate of the Reaction?The rate of reaction is defined as the rate of change of concentration of product and the concentration of reactant.
Let us considered a chemical reaction:
A → B
It can also be said that, rate of reaction is directly proportional to the concentration of reactant.
R = δ[B]/δt = -δ[A]/δt
Rate of the product is always positive because the concentration of the product always increases with time.
Thus, we concluded that due to continue decrease in the concentration of the reactant goes with time to form product, the rate of reaction expressed with a negative sign.
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