Hydroelectric power is one of the oldest and most widely used renewable sources of energy.
Globally we see that hydropower is by far the largest modern renewable source. Every country's top priority is to generate hydroelectric power so they have to rely less on nuclear and coal power plants.
Hydroelectric power is generated by using the elevation difference, created by a dam or diversion-like structure of water flowing in on one side and out, far below, on the other side.
If we talk about some countries, Hydropower currently generates 31.5% of total U.S. renewable electricity generation.
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Which of the following would be a reasonable unit for the rate constant of a second order reaction?
1. mol/L.sec
2. mol2/sec.L2
3. 1/sec
4. L/mol.sec
5. L2/mol2.sec
Option (4) is correct. The rate constant of a second order reaction has the unit L/mole. sec.
In the Second order reaction the rate is proportional to the square of the concentration of one reactant. Rate of Second order reaction is proportional to the product of the concentrations of two reactants. Such reactions generally have the form,
A + B → products.
Each monomer combines to form a larger molecule is called dimer. For the units of the reaction rate to be moles per liter per second (M/s), the units of a second-order rate constant must be the inverse (M−1·s−1). Because the units of molarity are expressed as mole/L, the unit of the rate constant can also be written as L(mole ·s).
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How many planes of cleavage does this mineral have? Choose one: A. 0 B. 2 at 90° intersections C. 3 not at 90° intersections D. 1
The planes of cleavage that the mineral have is 1 as the mineral name is Muscovite mica.
The crystal lattice structure of a mineral affects its propensity to split or break along flat planar faces, or cleavage. These 2D surfaces, also known as cleavage planes, are produced by the alignment of atoms in the crystal structure or lattice through relatively weak connections.
The mineral depicted in the image is called "Muscovite mica," and it has layers that seem like flat sheets. Muscovite mica is far more likely to break along the layers because it only has weakly bonded potassium ions. There is just one ideal cleavage plane as a result. This cleavage is evident in the capacity to peel mica sheets.
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2POCl3(g)---> 2PCl3(g)+O2(g), deltaH_o=572 kJ, delta S_o=179 J/K
At what temperature (if any) would the decomposition of POCl3 become spontaneous?
At T=3195.53 Kelvin, decomposition of PoCl3 becomes spontaneous.
What is meant by spontaneous?In chemistry, spontaneous processes is one that occurs without addition of external energy. Spontaneous process can occur quickly or slowly, because spontaneity is not related to the kinetics or reaction rate.
Spontaneous reaction happens in given set of conditions without interruptions whereas the nonspontaneous reaction occurs with the help of external agents like heat or energy.
Given, ∆H=572KJ and ∆S=0.179J/K
According to thermodynamical concept;
As, T=∆H/∆S,
=572/0.179
= 3195.53 Kelvin
We know, change in Gibbs free energy (∆G)=0 ; which shows that reaction is in equilibrium.
Above this temperature the reaction becomes spontaneous and moves in forward direction.
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A student dissolved 0.178 grams of a solid monoprotic acid in water and then titrated it. They then performed the same calculation as you just did in question 2 to find the moles and they found that 0.00685 moles were neutralized. What is the molar mass of the unknown acid that was dissolved? (Hint: What are the units for molar mass?)
Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 25.98g/mol is the molar mass of the unknown acid that was dissolved.
What is mole?The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number.
Mathematically,
mole =given mass ÷ molar mass
Molar mass of unknown acid= ?
mass of unknown acid= 0.178 grams
moles of unknown acid= 0.00685 moles
Substituting the values in above formula we get
0.00685 = 0.178 ÷ molar mass
molar mass=25.98g/mol
Therefore, 25.98g/mol is the molar mass of the unknown acid that was dissolved.
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What is a proposed explanation for an observation? A. experiemnt B. hypothesis C. theory D. scientific law
A proposed explanation for an observation is theory. Option C is the correct answer.
What is a theory?This refers to a carefully articulated explanation for observations of the natural world that have been arranged using the scientific method, gathering many facts and hypotheses.
A proposed explanation for an observation is a statement or theory that attempts to explain or account for an observation. It is a possible explanation for a phenomenon and is often based on available evidence, research, and data. It may be tested and refined through further observation and experimentation to determine its accuracy and validity.
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Explain what it means for materials to move down their concentration gradient and up their concentration gradient.
Moving down the concentration gradient means that materials move from an area of high concentration of the material to an area of low concentration of the material.
What is concentration?In chemistry, concentration is the amount of a substance in a given space. Another way to describe concentration is the proportion of the solute to a solvent or entire solution. In general, mass/unit volume is used to express concentration. Instead of using volume, concentration can be stated as a mass per unit. Although concentration is typically used to describe chemical solutions, it may be computed for any mixture.
This can be seen in osmosis, where water moves from a higher concentration of solute to a lower concentration of solute.
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Which of the following properties of covalent compounds are influenced by ionic character?
a. melting point
b. boiling point
c. viscosity
d. all of the above
The property of the covalent compound that is influenced by ionic character is boiling point. Option B
What is the ionic character?We know that for compounds, the kind of bonds that they have are usually neither here nor there. The bonds would have an ionic character and also a given amount of the covalent character.
We must note that the ionic character of a bond is very important when we discuss intermolecular interactions and they do affect the boiling points of the substances very much.
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Is this water or oil
Answer:
it is oil.
Explanation:
it is oil because if water was written that would be wried so I think it is oil.
Which of the following substances would you expect to have a nonzero dipole moment? Check all that apply.
O Chloroethane, CH3 CH2C1 O XeF4 O Cl20
BF3
O Chloroethane, CH3CH2Cl, O XeF4 of the following substances would expect to have a nonzero dipole moment
A substance with a non-zero dipole moment means that the electrons are not distributed symmetrically in the molecule, resulting in a partial positive charge on one end and a partial negative charge on the other end. Chloroethane, CH3CH2Cl has a polar covalent bond between C-Cl and since the C-Cl bond is polar the overall molecule is polar and thus has a nonzero dipole moment.O Chloroethane, CH3 CH2C1 O XeF4 O Cl20. BF3XeF4 has a tetrahedral electron pair geometry, with 4 polar covalent bond Xe-F, and since all the F atoms are in the same plane as the Xe atom, the molecule is polar and thus has a nonzero dipole moment. Cl20 has a polar covalent bond Cl-Cl but since the molecule is symmetric the overall dipole moment is zero. BF3 has a trigonal planar electron pair geometry, with 3 polar covalent bond B-F, but since the molecule is symmetric the overall dipole moment is zero.
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Gaseous ammonia chemically reacts with oxygen O2 gas to produce nitrogen monoxide gas and water vapor. Calculate the moles of water produced by the reaction of 0.90mol of ammonia. Be sure your answer has a unit symbol, if necessary, and round it to 2 significant digits.
1.08 moles of water () produced by the reaction of 0.90mol of oxygen.
Explanation:
Moles of oxygen given = 0.90 mole
Moles of water are to be calculated.
Step 1 : Write the chemical reaction and balance it.
5 mole of reacts with 4 mole of to give 4 moles of NO and 6 moles of .
Step 2 : Calculate moles of water () utilising mole ratio.
The coefficient of is 6 and coefficient of is 5, So mole ratio of to is 6 : 5
Moles of = 0.90 × 6 (moles of ) ÷ 5 (moles of )
Moles of = 1.08 moles
1.08 moles of is produced by the reaction of 0.90 mole oxygen ()
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when a set amount of marble chips (caco3) is added to a small amount of dilute hydrochloric acid, a reaction occurs. what should be done to decrease the rate of reaction the next time the experiment is performed
A tiny amount of weak hydrochloric acid is mixed with a quantity of marble chips (CaCO3), to decrease the rate of reaction we do decreasing the surface area of the marble chips, decreasing conc. HCL and many more.
Several ways are:-
1. Decreasing the surface area of the marble chips: By breaking the marble chips into smaller pieces, the surface area that is available for the acid to react with is reduced, slowing down the reaction.
2. Decreasing the concentration of the hydrochloric acid: By using a less concentrated solution of hydrochloric acid, the number of acid molecules available to react with the marble chips is reduced, slowing down the reaction.
3. Increasing the temperature: By performing the reaction at a lower temperature, the kinetic energy of the acid and marble chip molecules is reduced, slowing down the rate of collision between them, which slows down the reaction.
4. Using a catalyst: Addition of a catalyst to the reaction can change the reaction mechanism and decrease the activation energy needed for the reaction to occur, thus slowing down the reaction.
5. Using an inhibitor: An inhibitor is a substance that slows down the reaction by binding to the enzyme or catalytic site and preventing the substrate from binding.
It's important to note that these methods may also affect the overall yield of the reaction, so it's essential to use the appropriate method(s) for the specific experiment and goals.
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How many ATP does ATP produce?
The bulk of ATP production occurs during cellular respiration within the mitochondrial matrix, producing around thirty-two ATP molecules for every molecule of oxidized glucose.
What is ATP?The energy currency of the cell is ATP (adenosine triphosphate). It is a natural chemical molecule made up of phosphate groups, adenine, and the sugar ribose. These molecules supply energy to the body's many metabolic operations. Therefore, it is dubbed "Energy Currency of the Cell". ATP can be utilized to store energy for future reactions or it can be used to pay for reactions when the cell need energy. Animals use ATP to store the energy received from food breakdown. Similarly, plants use ATP molecules to collect and store the energy they receive from light during photosynthesis.
Here,
The majority of ATP is produced during cellular respiration within the mitochondrial matrix, which produces around thirty-two ATP molecules for every molecule of oxidized glucose.
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PbO + NaOH →→
complete and balance the following formula
Answer:
Explanation:
Pb(OH)2 + 2NaOH → Pb(OH)2 + 2NaOH
The balanced equation would be PbO + 2NaOH → Pb(OH)2 + Na2O
The reactant PbO is a lead oxide which is an acidic oxide, it reacts with NaOH, a strong base, to form Pb(OH)2, a lead hydroxide, which is a salt of lead, and Na2O which is sodium oxide , a base.
the safety air bag in automobiles are inflated by nitrogen gas by the rapid decomposition of sodium azide:
sodium azide (NaN3) is used to inflate the safety airbags in automobiles (g) This airbag should be filled with N2 at a pressure of 1.15 atm and temperature of 26.0°C. It has a volume of 36 L.
Modern automobiles use numerous technical components and subsystems, each of which performs a specific design function. Some of these have thousands of individual pieces and were made possible by new or improved technologies, such as electronic computers, high-strength polymers, and novel alloys of steel and nonferrous metals. Air pollution, safety regulations, and global manufacturer competition, among other things, have all contributed to the development of some subsystems.
With an estimated 1.4 billion in use worldwide, passenger vehicles have become the main form of family transportation. In the United States, where more than three trillion miles (almost five trillion kilometers) are traveled annually, roughly one-fourth of these are located.
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For each of the following chemical equations, write all possible mole ratios. a. 2HgO(s) → 2Hg(l ) + O2(g) b. 4NH3(g) + 6NO(g) → 5N2(g) + 6H2O(l ) c. 2Al(s) + 3H2SO4(aq) → Al2(SO4)3(aq) + 3H2(g)
What is c. 2Al(s) + 3H2SO4(aq) → Al2(SO4)3(aq) + 3H2(g)
a) The mole ratio is 2/1
b) The mole ratio is 4/6
c) The mole ratio is 2/3
What is the mole ratio?We have to note that the mole ratio is the ratio of the stoichiometric coefficient that we have between two reactants that can be found in an equation. In the case of the reaction equations that we have, we must look closely at each equation.
As we can see, each of the reaction equations is balanced and we can now be able to obtain the mole ratio of each of the reaction as shown in the answer above.
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How many ATP does glycolysis produce 4 ATP?
Energy is released when glycolysis occurs, and this energy is utilized to create four molecules of ATP. As a result, glycolysis produces a net gain of two ATP molecules.
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,
When glycolysis happens, energy is released, and this energy is used to build four molecules of ATP. As a result of this, glycolysis generates a net gain of two ATP molecules.
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Early chemists, known at the time as alchemists, had a difficult time understanding the Law of Conservation of Mass. Using the burning of wood as an example, what property of matter made this law difficult for early scientists to understand?
Different types of wood burned differently.
Wood is heavier than ash.
The fire was too bright to observe the reaction.
The gases produced escaped to the atmosphere.
Answer:
The gases produced escaped to the atmosphere.
Calculate the moles in 8334 grams of krypton, show work
What are two characteristics of the rock found 3 mya?
To solve this we must be knowing each and every concept related to rock and its characteristics. Therefore, the two characteristics of the rock can be given as below.
What is rock?The word rock relates to the material's bulk volume, which includes the grain or crystals in addition to the enclosed vacuum space.
The two characteristics of the rock are:
Some minerals exhibit color features related to mineral composition and atom arrangement: for example, magnetite is black, chlorite is green, and pyrite is brassy yellow.
The capacity of a mineral to resist scratching is used to estimate its hardness, which is generally determined on fresh material. When a mineral is scraped with a knife, it softens. If a knife cannot scratch it, the two have equivalent hardness or even the mineral is harder.
Therefore, the two characteristics of the rock can be given as above.
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What is the pH of a 7.5 × 10-3 M Ba(OH)2 solution at 25°C?
a. 0.015
b. 1.82
c. 12.18
d. 11.88
A 7.5 10-3 M Ba(OH)2 solutions at 25°C has a pH of 1.82. (option b).
What exactly is a solution exemplar?A homogenous solution of two or more ingredients with particles smaller than one nm is referred to as a solution. Solutions come in many forms, such as soda water, salt and sugar solutions, etc. In a solution, every element appears as a single phase.
What is the ideal definition of a solution?In chemistry, a solution is a homogeneous mix of two or more molecules in relative proportions that can be constantly changed up to what is known as the limit of solubility. Although the term "solution" is frequently used to refer to the liquid state of matter, solutions of gases and solids are also possible.
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An oxygen-binding protein was purified from a mollusk. It was found to exhibit fluorescence, which means that it has amino acid residues that absorb light of one wavelength and then emit light of a longer wavelength. Generally, the more exposed these residues are to solvent, the greater their fluorescence intensity. When placed in a deoxygenated buffer solution, the protein's fluorescence was measured and assigned a value of 1.0. Then the amount of protein fluorescence was measured under various other conditions and expressed relative to the initial measurement. The results are summarized in the table. Which conclusion is supported by these results
The conclusion is supported by these results is binding of oxygen to the protein changes the protein's tertiary structure to a conformation that resists the effects of urea.
Simple definition of fluorescenceFluorescence is a property that some chemicals have that allows them to emit visible light after absorbing radiation that is typically invisible, like ultraviolet light.
Fluorescence is the name given to the process of electromagnetic radiation typically visible light emitting from a material as a result of atoms being excited. These excited atoms almost immediately (within 10⁻⁸ seconds) begin emitting again. In most cases, the initial excitation is brought on by the energy absorption of incident radiation or particles, like X-rays or electrons.
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What is the cause of periodic repetition of properties of elements?
The periodic repetition of properties of elements is due to the regular arrangement of electrons in the atoms of those elements. This regular arrangement is known as the "periodic table" of elements. This is due to the behavior of electrons in atoms and the increasing number of valence electrons as atomic number increases, resulting in a regular pattern of electron configurations and properties.
Elements are arranged in the periodic table according to increasing atomic number. Elements in the same vertical row (group) have similar chemical and physical properties, and elements in the same horizontal row (period) have similar electronic configurations of their atoms.
The reason for this repeating periodic property is the behavior of the electrons in the atoms. As the atomic number increases, the number of protons in the nucleus increases, and the number of electrons in the atom increases. These electrons occupy different energy levels or shells around the atomic nucleus. The outermost shell electrons, the so-called valence electrons, are responsible for the chemical behavior of atoms and participate in chemical bonds. As the atomic number increases, the number of valence electrons in the atom increases. This results in a regular pattern of electron configurations and thus a regular pattern of properties.
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What is measuring tools for sewing?
Measuring tools like Clear ruler, yardstick, measuring tape etc. They are very useful for the perfect fit and shape of any garment and even home furnishing.
Sewing is the craft of fastening or attaching objects using stitches which is made up of a sewing needle and thread.
Measuring tools are the instruments used by practitioners and researches to aid in the assessment or evaluation of the subjects, clients or patients etc. These instruments are used to measure or collect the data on a variety of variables ranging from psychosocial wellbeing or physical functioning.
Measuring tools in sewing are as follows: Measuring tape, clear ruler, quilting ruler, yardstick, French curve etc.
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A car has a mass of 2,050 kg and is traveling at 28 meters per second. What is the car's kinetic energy?
After solving the equation the car's kinetic energy is 783,500 kg m2/s2.
What is kinetic energy?Kinetic energy is the energy of motion, or the energy associated with an object or system due to its motion. It is a form of energy that can be converted into other forms of energy, such as thermal energy, sound energy, electrical energy, and so on.
The car's kinetic energy is the energy it has due to its motion. Kinetic energy is calculated as KE = 1/2mv2, where m is mass and v is velocity. In this case, the car has a mass of 2,050 kg and is traveling at 28 meters per second. Plugging these values into the equation gives:
KE = 1/2(2050 kg)(28 m/s)2
= 1/2(2050 kg)(784 m2/s2)
= 783500 kg m2/s2
Therefore, the car's kinetic energy is 783,500 kg m2/s2.
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The function t=f(a) models the time, in minutes, for a chemical reaction to occur as a function of the amount a of catalyst used, measured in milliliters. What are the units for f′′(a) ?
The unit of f''(a) is milliliters/minute^2
The function t=f(a) models the time, in minutes, for a chemical reaction to occur as a function of the amount a of catalyst used, measured in milliliters.
So, here double differentiation is to be done.
t=f(a)
differentiating with respect to t,
d(t)/dt = d(f'(a))/dt
or, d(f'(a))/dt = 1
again differentiating with respect to t,
d [d(f'(a))/dt]/dt = d(1)/dt = 0 ...1
or, f''(a) = 0
so, here if we put 'unit expression' in Left hand side of 1
it is d [d(f'(a))/dt]/dt i.e. mililiters/miniute/minute [as given t is measured in minute and f(a) is measured in ml)
or, ml/minute^2
so as we are performing double differentiation, the unit of f''(a) is milliliters/minute^2
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The following reaction occurred when a strip of aluminum was placed in a nickel solution. Which half-reaction represents the oxidation that has occurred in the reaction?
The reaction that shows oxidation is the one that has been shown in option D.
What is oxidation?We have to know that the process that we call oxidation would have to do with the loss of the electrons that we have in a system. If we are dealing with a neutral atom that has been oxidized then we would see an increase in the oxidation number of the atom. This same effect would be seen if we are looking at the oxidation of any other chemical specie that is under consideration.
Ni lost and electronNi^2+ was formedA total of two electrons were lost in the process.We need to look at the reactions that have been shown in the options that we have and then compare it with the overall redox reaction equation that we see at it has been shown in the reaction that has been attached to the question that we have in the attachment that is shown above here.
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Entropy and the inefficiency of energy transfer are part of __________________. the first law of thermodynamics the second law of thermodynamics the third law of thermodynamics system resiliency feedback systems
Entropy and the inefficiency of energy transfer are part of the Second Law of Thermodynamics.
The first law of thermodynamics states that neither creation nor destruction of energy is possible. The universe becomes more entropic when a spontaneous process occurs, according to the second law of thermodynamics. Thermodynamics' third law: The entropy of a perfect crystal is 0 at absolute zero Kelvin. The overall entropy of a system may only ever increase or stay constant during spontaneous processes, according to the second law of thermodynamics. If the physical process is irreversible, the overall entropy of the system and its surroundings must increase. For a process to be irreversible, the final entropy needs to be higher than the starting entropy: Sf > Si (irreversible process). The overall entropy of a system and its surroundings can remain constant when a system is in thermodynamic equilibrium or undergoing a reversible process. The second law is sometimes known as the Law of Increased Entropy.
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How many grams are in 2.5 moles of KCl
Answer:
186.25
Explanation:
KCL= 74.5 (molar mass)
2.5*74.5= 186.25
Sulfuryl chloride is in equilibrium with sulfur dioxide and chlorine gas: so2cl2(g) so2(g) + cl2(g) a system with a volume of 1. 00 l is in equilibrium at a certain temperature with p(so2cl2) = 1. 00 bar and p(so2) = p(cl2) = 0. 10 bar. By how much will the number of moles of so2cl2 at equilibrium change if the volume is reduced to 0. 50 l? (a) increase 1-10% (b) increase 11-50% (c) decrease 1-10% (d) decrease 11-50%
The volume is decreased to 0. 50L, the number of moles of SO₂Cl₂at equilibrium will increase by 1–10% option - a is correct.
What is Le Chatelier's Principle.The guiding idea of Le Chatelier is as follows: A shift in the position of the equilibrium results from a change in one of the variables that characterize a system in equilibrium and cancels out the effects of that change.
Now to solve this question first we have to know the Le-chatelier's
Principle
The Principal that if a system in chemical equilibrium is subjected to a disturbance it tends to change in a way that opposes this disturbance.
SO₂Cl₂(g) ⇄ SO₂(g) + Cl₂(g)
Initially, there is one molecule at the left hand side of the reaction and two molecules are on the right. But, the Partial pressure of molecules on RHS is lower than LHS. Concentration of RHS molecules is Lower, forward reaction is more favorable.
Decreasing volume would result in increasing the total pressure.
Now, according to Le chatelier's Principle, the equilibrium will shift in such a way to oppose change under compression. Since there are more moles of Products than reactants, to counteract the increased pressure. The equilibrium will shift to LHS increasing the moles
of SO₂Cl₂ but since the concentration (Partial Pressure)
of SO₂Cl₂, it will not increase more than 10%
Hence, answer will be (a) Increase 1-10%.
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How did the experiement with boiling water compare with the experiment in which magnesium was added to hydrochloric acid
In the experiment with boiling water and the experiment in which magnesium was added to hydrochloric acid both resulted in gas formation.
Hydrochloric acid and magnesium in a balanced chemical reaction
[tex]MgCl_{2}[/tex] + [tex]H_{2}[/tex] = Mg + 2HCl (g).
A gas is hydrogen . This reaction is exothermic (energy is released). New compounds are being produced due to chemical change.
Nothing new is created when water is heated to a boil. Heat is added in this endothermic reaction. Gas is steam. Both experiments a gas is released. One is a chemical change the other is a physical change. One is exothermic while other is endothermic.
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