In reality, spontaneous reactions occur relatively slowly because The reaction's activation energy is high.
Hence, Option 1 is correct.
A spontaneous reaction is one that favors the creation of products in the environment in which it is taking place.Given that spontaneous reactions discharge free energy, the sign of G must be negative. There are four distinct conceivable combinations because both H and S can be either positive or negative depending on the features of the specific reaction.An exothermic example of a spontaneous reaction is a raging campfire (there is a decrease in the energy of the system as energy is released to the surroundings as heat).Find more information about Activation energy here:
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mendeleev is given the most credit for the concept of a periodic table of the elements because:
Mendeleev is given the most credit for the concept of a periodic table of the elements because he emphasized its usefulness in predicting the existence and properties of unknown elements.
What is Periodic table?This is referred to as a tabular arrangement of the chemical elements by increasing atomic number which displays the elements so that one may see trends in their properties.
It consists of a rows and columns arrangement of the chemical elements and each they are grouped according ti the similar features which are present in the elements.
Mendeleev was the scientist who was given the most credit for the concept of a periodic table of the elements despite others working on it previously as a result of his emphasis in its usefulness in predicting the existence and properties of unknown elements.
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How many ATP's is produced in the glycolysis of 2 glucose molecules?
Answer: 4 ATP molecules is produced in the glycolysis of 2 glucose molecules
How is ATP produced?The first stage of most carbohydrate catabolism, which is described as the breakdown of larger molecules into smaller ones, is glycolysis, which is a part of cellular respiration. Two Greek words that mean "to break down anything sweet" are the source of the word glycolysis. Two molecules of ATP are created during the breakdown of glucose and formation of pyruvate during glycolysis.
Explanation:
2 ATP are produced.
For every glucose molecule, meaning that for every 2 glucose molecules, 4 ATP will be created.
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Which isotope, when bombarded with nitrogen-15, yields the artificial isotope dubnium-260 plus 4 neutrons
The isotope that when bombarded with nitrogen-15 yields the artificial isotope dubnium-260 plus 4 neutrons is californium-249.
Californium-249 is a heavy element and when bombarded with nitrogen-15, which is a light element, undergoes a nuclear reaction known as a "cold" fusion reaction. This reaction results in the formation of the artificial isotope dubnium-260, which has a higher atomic number than the starting element and the release of 4 neutrons.This process is known as a Nuclear Transmutation, which is a process in which one element is converted into another element by bombarding it with a beam of particles such as protons, neutrons, or other ions.
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How many grams is 0.5 moles?
0.5 moles of carbon weigh 6.0055 grams.
One of the chemical elements is carbon. The letter C stands for carbon, and the letter g stands for grams. As a result, 0.5 moles of carbon per gram is equivalent to 0.5 moles of carbon per gram, 0.5 moles of carbon per gram, and 0.5 moles of C per gram.
Carbon has a 12.011 atomic mass. Thus, one mole of carbon has a mass of 12.011 grams (12.011 g/mol). We multiply 0.5 moles of carbon by 12.011 to get grams, and vice versa.
no. of Grams = Moles of Carbon x 12.011
=0.5 × 12.011 = 6.0055
0.5 moles of carbon equal 6.0055 grams.
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The complete question is
How many grams is 0.5 moles of carbon
In the lab, the dominant phenotype for sheep color is wool and the recessive phenotype for sheep color is wool
The dominant phenotype for sheep color is wool because it is the most common color seen in sheep.
What do you mean by Phenotype?
Phenotype is the physical, biochemical, and physiological characteristics of an organism, as determined by both genetic makeup and environmental influences. It is the physical expression of an organism's genes, and can be seen in its morphology, development, and behavior.
Wool is usually white or off-white in color and is the result of a dominant gene. The recessive phenotype for sheep color is non-wool, which is usually a darker color, such as black, brown, or gray. This is the result of a recessive gene and is less common than the dominant gene.
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how many liters of water can be made from 55 grams of oxygen gas and an excess of hydrogen at a pressure of 12.4 atm
At a pressure of 12.4 atm and a temperature of 850 c, 8.2 liters of water can be created from 55 grams of oxygen gas and an excess of hydrogen.
first, we need the no.of moles of O2 = mass/molar mass of O2
= 55 g / 32 g/mol
= 1.72 mol
from the balanced equation of the reaction:
2H2 (g) + O2(g) → 2H2O(g)
we can see that the molar ratio between O2: H2O = 1: 2
So we can get the no.of moles of H2O = 2 * moles of O2
= 2 * 1.72 mol
= 3.44 mol
So by substitution by this value in the ideal gas formula:
PV = nRT
when P = 12.4 atm & n H2O = 3.44 mol & R= 0.0821 & T = 85 + 273=358K
12.4 atm *V = 3.44 * 0.0821 * 358 = 8.15 L
∴ V ≈ 8.2 L
In the physical sciences, pressure is defined as the perpendicular force per unit area or stress at a point within a confined fluid. The pressure exerted on a floor by a 42-pound box with a bottom area of 84 square inches is equal to the force divided by the area over which it is exerted, or one-half pound per square inch.
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Show all your work and make sure to label all the numbers with the correct units if you do, I will give you brainliest, 5 stars, and a thank you:
A: A sample of sulfuric acid has a mass of 15.0 g. How many molecules are in this sample?
B: How many moles of sulfuric acid are present in 45 g of this sample?
C: How much would a .750 mole sample of Ammonium sulfate weigh?
D: What is the mass percent of hydrogen in this sample?
1
4
2
What are the relative masses of a proton, neutron
and electron, given that a proton has a mass of 1?
How many protons, neutrons and electrons are
there in an atom of phosphorus, which has a proton
number of 15 and a mass number of 31?
3
Explain the terms atom and element, and include
a clear description of the relationship between the
two terms.
Explain why neutrons are important in making the
nucleus of an atom stable. You need to consider the
charges on the different subatomic particles present.
Answer:
Explanation:
A proton has a relative mass of 1. A neutron has a relative mass of 1. An electron has a relative mass of 1/1840. (accept 0)
An atom of phosphorus, which has a proton mass number of 31 has 15 protons, 15 electrons, and 16 neutrons.
Atom- The fundamental units of matter are atoms. They have a single nucleus, which is surrounded by a small number of protons and electrons.
Element- A species of atom known as an element is one that cannot decompose further. They only contain one kind of atom with the same quantity of protons.
Role of Neutron-
Neutron's charge is neutral. The element's mass is made up of protons and neutrons.
The neutrons' main function in an atom's nucleus is to contribute to the nuclear glue or binding energy that binds the nucleus itself together. Remember that protons and neutrons make up an atomic nucleus.
Positively charged protons don't get along with one another.
Neutrons are added to the structure to make up for the so-called mass deficit in order to counteract the protons' attractive forces.
In order to keep the nucleus together, the nucleons—the protons and neutrons in a nucleus—lose a little bit of mass that is transformed into binding energy.
Proton has relative mass of 1 while neutron has relative mass of 1. While that of an electron has relative mass of 1/1840.In phosphorous there are 15 electrons , protons and 16 neutrons.Atoms of same type combine to form element.Neutrons contribute to mass of atom hence change in number will make atom unstable.
What is an atom?An atom is defined as the smallest unit of matter which forms an element. Every form of matter whether solid,liquid , gas consists of atoms . Each atom has a nucleus which is composed of protons and neutrons and shells in which the electrons revolve.
The protons are positively charged and neutrons are neutral and hence the nucleus is positively charged. The electrons which revolve around the nucleus are negatively charged and hence the atom as a whole is neutral and stable due to presence of oppositely charged particles.
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Which sample of matter has the lowest average kinetic
energy?
O 50. g at -55°C and 2.0 atm
O 50. g at 273 K and 4.0 atm
O 50. g at 33°C and 3.0 atm
O 50. g at 367 K and 1.0 atm
The given sample of matter has the lowest average kinetic energy is 50g at -55°C and 2.0 atm option - A is correct answer.
What exactly is kinetic energy?The force an object experiences as a result of motion is known as kinetic energy. An object can only accelerate if a force is applied to it. We have to put in the effort to use force. Once the work is done, energy is transferred to the object, which then moves at a new, constant speed.
Kinetic energy, which can be seen in the motion of an object or subatomic particle, is the energy of motion.
The average kinetic energy is the subject of the query. Thus, the only connection is to temperature. Kinetic energy increases with increasing temperature and decreases with decreasing temperature.
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F app F fric F norm F grav Which statement best describes the forces shown in this picture? A. The force of friction and the gravitational force are balanced. B. The force of friction is less than the applied force. C. The normal force and the gravitational force are balanced. D. All four forces are acting on the student.
He is not falling nor about to fall which means he’s perfectly balanced. So this means the force in the photo and friction in this photo is in a balanced condition, balancing the boy.
How forces are balanced?In the given picture, the applied force and the force of friction are balanced. if two forces act in the direction to make the object in a balanced state.
If the forces are in a balanced state it does not change the motion of the object, and if it is in an unbalanced state, it causes to change in the state of the motion.
Therefore, the force of friction and the gravitational force are balanced is the correct option.
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The given question is incomplete, so the complete question image is attached in the image below.
1. How many moles of propane are present at STP if the volume is 65.0 L? Please show all work
Answer:
Therefore, there are 4.47 moles of propane present at STP in a volume of 65.0 L
Explanation:
First, we need to calculate the number of moles of propane present at STP. At STP, the temperature is 273 K and the pressure is 1 atm.
Using the Ideal Gas Law, we can calculate the number of moles of propane present in the given volume.
PV = nRT
n = 4.47 mol
Therefore, there are 4.47 moles of propane present at STP in a volume of 65.0 L
A sealed, insulated calorimeter contains water at 310 K. The surrounding air temperature is 298 K, and the water inside the calorimeter remains at 310 K two hours later. What type of system does the calorimeter attempt to model
There is no heat exchange with the environment since the calorimeter is insulated. This may be demonstrated by saying: Since the calorimeter is a fixed unit, it follows that its heat capacity likewise has a fixed value.
Calorimeters are the tools used to measure the amount of heat. The definitions of heat and temperature, the quantity of heat absorbed to raise a body's temperature, the distinction between heat and temperature, and specific heat capacity are among the fundamental ideas presented in this chapter. A chemical reaction's associated thermal energy change is what causes a calorimeter's temperature to fluctuate. If the calorimeter absorbs heat (q calorimeter > 0) and its temperature rises, the reaction is producing heat (q rxn 0).
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Tungsten 188 decays by beta. Find the daughter product.
daughter product (mass.atomic/,element symbol);
By beta, tungsten 188 decays. The mechanism through which an insecure atomic structure is produced is known as radioactive decay.
How does radioactive decay work?The process through which highly unstable molecular nucleus loses its energy through radiation is described as radioactive decay, also characterized as nuclear decay, radiography, radioactivity breakdown, or nuclear disintegration. A substance that has unstable nuclei is regarded as radioactive. For a large variety of human activities, radioactive decay is crucial.
What occurs when radioactive material decays?Alpha, beta, and/or gamma rays are all types of ionizing radiation that are released when radioactive atoms decay. Because the energy is powerful enough to dislodge firmly coupled electrons from just an atom's orbit, it is known as ionizing radiation. As a result, the atom develops into a charged ion.
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calculate the solubility of AgCN in a solution containing 1.0M H Ksp of AgCN is 2.2e-12 Ka of HCN is 6.2e-10
The solubility of AgCN in a solution containing 1.0M H Ksp of AgCN is 2.2e-12 Ka of HCN is 6.2e-10 is 5.9 x 10^-2M.
Given concentration of H+ (M) = 1.0M
Ksp of AgCN = 2.2e-12
Ka of HCN = 6.2e-10
AgCN ⇋ Ag+ +CN− ................Ksp
CN − + H+ ⇋ HCN................... 1/Ka
AgCN + H+ ⇋ HCN + Ag+ ...................Ksp/Ka = K0
K0 = 2.2e-12/6.2e-10 = 0.0035 = 35 x 10-4
At Equilibrium: AgCN + H+ ⇋ HCN + Ag+
Let the moles of [Ag+] = x
So the number of moles of [HCN] = x
K0 = [Ag+] [HCN] / [H+]
35 x 10-4 = x^2/1
x = 5.9 x 10^-2M
Hence the molar solubility of AgCN in buffer solution is 5.9 x 10^-2M.
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An extremely efficient enzyme has a ____ KM and a ____ kcat.
An extremely efficient enzyme has a small KM and a large kcat.
The conversion rate at the lowest substrate concentration is measured in kcat/km. This interpretation is accurate. kcat/Km is a good indicator of an enzyme's effectiveness since it takes into account both the enzyme's maximum rate, kcat, and its affinity for its substrate (Km).The turnover number, or the number of molecules that may be created per second per active site, of an enzyme is provided by the formula k c a t / kM.Because the substrate concentration is almost usually much greater than the Km, in many situations, enzymes are only better when they have a larger kcat. It seems disingenuous to me to use the ratio when this is plainly the case, yet it still happens much too frequently. It could serve as a useful benchmark when compared to enzymes in particular situations.
complete question:An extremely efficient enzyme has a _____ KM and a _____ kcat.
A) small; small
B) small; large
C) large; large
D) large; small
E) kcat and KM do nothing to predict the efficiency of an enzyme
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Would using king size bags of M&M's make a difference to the average "atomic mass"? Why or why not?
No, because every M&M's is identical.
M&M's contain the same amount of protons, M&M's are the same hue. In other words, the size represents the various neutron counts.
Atoms of the same chemical element called isotopes each have a distinct mass number.
While isotopes can vary in mass, they never do so in atomic number (the amount of protons). You will use M&Ms to represent atoms because we are unable to see them. These objectives are use in M&Ms to determine the average atomic mass and to observe how different isotopes are.
In this the number show how many M&M's of that color and size are packed into that bags.
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what percent composition tell you about a molecule
Answer:
tells you by mass what percent of each element is present in a compound.
Explanation:
Which of the following combinations could be linked together to form a nucleotide?
A) 1, 2, and 11
B) 3, 7, and 8
C) 5, 9, and 10
D) 11, 12, and 13
E) 12, 14, and 15
In order to produce a nucleotide, the combinations 11, 12, and 13 may be combined.
The definition and purpose of a nucleotideThe basic unit of DNA and RNA are nucleotides. Genetic material is present in them. Since many biological reactions involving enzymes require coenzymes, nucleotides serve in this capacity. ATP serves as the body's energy storage system.
How does DNA get made up of nucleotides?A phosphodiester bond forms when the 5' phosphate group of one nucleotide and the 3'-OH group of another nucleotide come together during the incorporation of nucleotides into DNA (see below). Phosphate-sugar-phosphate-sugar-phosphate forms the "backbone" of each DNA strand in this way.
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Rusting as a redox reaction in details
The reactant is iron (Fe) and the oxidizing agent is oxygen (O). This reaction results in the the formation of a compound known as iron oxide (Fe2O3), which is commonly referred to as rust. The reaction can be written as:
Fe + O2 --> Fe2O3
The oxidation process involves the loss of electrons from the Fe atoms, as oxygen gains electrons and is reduced. The electrons are transferred from the iron to the oxygen, resulting in the formation of iron oxide, which is an insoluble solid.
An oxidation-reduction reaction, or redox reaction, is a reaction in which there is a transfer of electrons between chemical species (the atoms, ions, or molecules involved in the reaction).
The reaction can be written as: [tex]\bold{Fe + O2 \Rightarrow Fe_2O_3}[/tex]
How many total ATP are produced during glycolysis ?
During glycolysis, each G3P produces two ATP, for a total of four ATP per glucose molecule.
What is glycolysis?The metabolic mechanism that transforms glucose to pyruvate is known as glycolysis. This free energy is utilized to create the high-energy molecules adenosine triphosphate and reduced nicotinamide adenine dinucleotide. Glycolysis is a series of 10 enzyme-catalyzed processes. The initial stage in the breakdown of glucose to extract energy for cellular metabolism is glycolysis. Glycolysis is divided into two phases: energy-requiring and energy-releasing. Glycolysis is the process of breaking down glucose to create energy. It generates two pyruvate molecules, ATP, NADH, and water. The process occurs in a cell's cytoplasm and does not require oxygen. It can be found in aerobic and anaerobic organisms.
Here,
Each G3P produces two ATP during glycolysis, for a total of four ATP per glucose molecule.
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A controlled experiment _____.Group of answer choicesIs repeated many times to ensure that the results are accurateProceeds at a slow pace to guarantee that the scientist can carefully observe all reactions and process all experimental dataIncludes at least two groups, one of which does not receive the experimental treatmentIncludes at least two groups, one differing from the other by two or more variables
An experimental group and a control group are both included in a controlled experiment. At least one of the two groups—the group that is not subjected to the experimental treatment—is present in a controlled experiment.
In controlled experiment, the researcher wants to determine how one or more variables affects on something. Since many different variables affecting the results, and most of them are not of interest to the researcher, and they will kept under control. They must remain constant. There must be at least of two groups. One of them is control group, and the other one is experimental group.
During experiment, a researcher compares between two groups. Both are composed of individuals which is coming from same population, so they are very identical in all the aspects except for independent variables that the researcher changes in to the experimental group and they observe that how they will affect the individuals. Control group is used to identify any of the other factors influencing the results which is obtained in the study, apart from the modified variables of the treatment. Independent variable keeps constant in control group.
The experimental group receives the treatment. The researcher voluntarily modifies the independent variable's values to see how it impacts the subjects. There can be several experimental groups.
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Which component of the periodic table is needed to determine why KCl tastes like NaCl? A. Group B. Period C. Atomic Weight D. Atomic Number
Atomic Number of the periodic table is needed to determine why KCl tastes like NaCl.
What is the Periodic Table?
The Periodic Table is a tabular arrangement of the chemical elements organized by atomic number, electron configuration, and recurring chemical properties. It is one of the most important tools in chemistry, providing a useful framework to classify, systematize, and predict the properties of elements.
Atomic numbers are used to identify each element in the periodic table, and they are also used to determine the number of protons in the nucleus of an atom. The number of protons in an atom determines its chemical properties, and the similarity in the number of protons between two elements can explain why they have similar properties. In this case, the similarity in the atomic number of potassium (K, atomic number 19) and sodium (Na, atomic number 11) explains why the salts of both elements, potassium chloride (KCl) and sodium chloride (NaCl), taste the same.
Hence, Option D is correct.
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What does 14 mean in c14?
14 mean in C14 is C14 has atomic mass of 14.
The radioactive carbon isotope with the longest half-life, carbon-14, whose decay enables precise dating of archaeological artifacts. Six protons and eight neutrons make up the carbon-14 nucleus, giving it an atomic mass of 14. Additionally, the isotope is employed as a tracer to monitor specific carbon atoms as they undergo chemical or biological changes.
The 14 in C14 represents the number of neutrons and protons in the nucleus of that atom or we can called it atomic mass. Carbon-14: with 6 protons and 8 neutrons, and an atomic mass of 14,
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Explain the similarities and differences between putting a beaker of ethanoic acid in the refrigerator and mixing it with sodium carbonate. Use these words: chemical,physical, reversible, irreversible.
When a beaker of ethanoic acid is placed in the refrigerator and mix it with sodium carbonate, its temperature drops down and endothermic reaction take place.
[tex]2CH_{3} COOH + NaCO_{3}[/tex] ⇒ [tex]CH_{3}COONa + NaHCO_{3}[/tex]
This chemical reaction is a reversible reaction.
Similarities:Ethanoic acid and sodium carbonate combine to form an endothermic reaction that results in fizzing as carbon dioxide is released and heat is lost to the environment, making the reaction vessel feel chilly to the touch.
Differences:The difference between adding sodium carbonate to the solution and refrigerating ethanoic acid is that no new substance is created in the former. When the substance is taken out of the refrigerator, it is still ethanoic acid. New chemicals are created in the latter scenario. Because of a chemical process, the material is no longer ethanoic acid.
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Methanol (methyl alcohol or wood alcohol) is a potential automotive fuel, either in pure form or mixed with gasoline. Some fleet vehicles, such as municipal buses, have been modified to burn methanol-containing fuels. These fuels are also used by some race cars. A particular automobile modified to use a mixture of 85.0% methanol and 15.0% gasoline by mass gets 25.5 mi/gal. The fuel has a density of 0.775 g/mL. How many kilograms of methanol does the automobile consume in a trip of 808 km
Answer:
it’s 4
Explanation:
Predict the ideal bond angles in GeCl4 using the molecular shape given by the VSEPR theory
>120°
109.5°
120°
<120°
>109.5°
90°
< 109.5°
180°
Predict the ideal bond angles in GeCl4 using the molecular shape given by the VSEPR theory is 109.5°.
Germanium tetrachloride has an odd, acidic smell and is a colorless, fuming liquid. It is a necessary step in the creation of pure germanium metal. GeCl4 has seen a significant rise in utilization recently as a result of its employment as a reagent in the creation of fiber optics. GeO2 (germanium dioxide) may be immediately converted into germanium tetrachloride by dissolving the oxide in strong hydrochloric acid. To purify and remove the germanium tetrachloride from other products and contaminants, the resultant liquid is fractionally distilled. Rehydrolyzing the GeCl4 with deionized water will yield pure GeO2, which may then be reduced with hydrogen to get germanium metal.
complete question:Predict the ideal bond angles in GeCl4 using the molecular shape given by the VSEPR theory
109.5°
90°
120°
180°
< 109.5°
>109.5°
<120°
>120°
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Which sample contains the greatest number of molecules?
A 4g of hydrogen
B 18 g of water
C 24 dm³ of oxygen
D 66 g of carbon dioxide
And why is the answer that way?
Answer:
4g of hydrogen
Explanation:
4g of hydrogen (molar mass 2) corresponds to 2 moles of molecules or 4N number of atoms where N is the Avogadro's number (6.023×10
23)
Heat conservation is important for polar endotherms, thus they tend to be _________ so that they __________ their surface area to volume
Polar endotherms must save heat, hence they usually have a significant surface area to volume ratio. The capacity to maintain blood is what makes heat conservation unique.
Vasoconstriction keeps it in the centre by decreasing blood flow to the outside (also known as peripheral vasoconstriction). An endotherm is an organism that uses heat produced by its internal biological processes rather than nearly exclusively relying on ambient heat to keep its body at a metabolically advantageous temperature. In thermodynamics, heat is defined as a kind of energy that crosses a thermodynamic system's boundary due to a temperature differential across the barrier. Heat is not present in a thermodynamic system.
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The reaction between NO(g) and O2(g) produces a single product. The reaction occurs in a rigid reaction vessel represented in the diagram above. Which of the following statements correctly predicts the change in average molecular velocity of the molecules as the reaction goes to completion at constant temperature and provides the correct explanation
The average molecular velocity of the molecules will decrease as the reaction goes to completion at a constant temperature.
What is Molecular velocity?
Molecular velocity is the average speed of molecules in a sample of matter. It is determined by the temperature of the sample, with higher temperatures resulting in higher molecular velocities.
This is because the reaction produces a single product, meaning that the number of molecules in the reaction vessel is decreasing as the reaction goes to completion. As the number of molecules decreases, the average molecular velocity of the molecules decreases as well.
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If you react 9.8 grams of Zn, how many moles of H2 can you make?