The statement scientists have discovered new planets orbiting a star by detecting a wobble in the star's motion shows how scientists use observations to gain a new understanding of the world (Option A).
What is a planet's orbit?A planet's orbit is a route that a planet as a celestial body has around its star in a star system. The orbit of a planet can be detected by observing the light emitted by the star, which is fundamental for astronomers.
Therefore, we can conclude that scientists discovered new planets through the identification of features associated with star's movement in space (Option A).
Complete question:
Scientists are always learning new things. Which of the following shows howscientists use observations to gain new understanding about the world?
A. Scientists have discovered new planets orbiting a star by
detecting a wobble in the star's motion.
B. Scientists hope to learn more about how many stars are in space.
C. Scientists wonder if other planets can support life, and some
scientists wonder if there are aliens.
D. Scientists are familiar with some galaxies, but they do not know
how many galaxies exist.
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A 5.0 Amp current is passed through a solution of copper (II) sulfate for four hours. How many grams of copper could form on the cathode during this process?
The amount of copper that would be deposited on the cathode during the process is 47.75 g.
What is the amount of copper (II) deposited?
The amount of copper (II) deposited is calculated as follows;
CuSO² ⇄ Cu²⁺ + SO₄²⁻
Cu²⁺ + 2e⁻ → Cu
.
From the oxidation reaction above, we can infer that,
2F -----------> 64 g of copper (Cu)
where;
F is Faraday = 96500 CThe quantity of charge passed through the solution of copper (II) sulfate for four hours is calculated as follows;
Q = It
where;
I is the currentt is the time of current flowQ = (5 A) x (4 hrs x 3600 s/hr)
Q = (5 A) x (14,400 s)
Q = 72,000 C
The amount of copper that will be deposited by this quantity of charge is calculated as follows;
96500 C --------> 64 g
72,000 C ---------> ?
= (72,000 X 64) / 96500
= 47.75 g
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What does the sun supply to a leaf?
starch
water
light energy
gas
The sun provides energy to the leaves through photosynthesis. It converts the sun's rays into sugar and provides energy to the leaves.
When sunlight hits the leaves packets of light called photons bounce off the chlorophyll molecules. In doing so it knocks electrons out of orbits around the magnesium atom. Electrons have a negative charge, so the loss of an electron produces a positively charged magnesium ion. Plants absorb energy from the sun through a process called photosynthesis to power processes necessary for survival.
Harvest the sun's energy with the help of chlorophyll in the cells of the leaves. Chlorophyll captures and packs energy from the sun's light in a process called photosynthesis. Leaves usually have a large surface area to maximize sunlight. Photosynthesis is the process by which plants use sunlight, water, and carbon dioxide to produce oxygen and energy in the form of sugars. The more light a plant is exposed to, the less chlorophyll it synthesizes.
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a sample of an unknown gas effuses in 10.7 min. an equal volume of h2 in the same apparatus under the same conditions effuses in 2.42 min. what is the molar mass of the unknown gas?
Molar mass of the unknown gas= 39.09 g / mol
T= TIME
MW= MOLAR MASS
MW H₂ = 2
now, Apply graham law--
graham law states that rate of effusion of a gas is inversely proportional to square root of the molar mass of its particle.
Rate1/rate2 = √(MW2/MW1)
T2/T1 =√(MW2/MW1) (BECAUSE, VOLUME EQUAL)
(10.7/2.42)²= MW2/2
MW2=molar mass of the unknown gas = 2α×(10.7/2.42)²
=39.09 g / mol
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Do you think everything in the solar system revolves around the sun?
Answer:
everything in OUR solar system revolves around the sun
Explanation:
the sun is the only star in our solar systen
Answer: Everything in our solar system revolves around the sun
Explanation: everything in our milky way revolves around the sun but in other solar systems it does not because that is a completely different solar system with most likely a different sun so yes in OUR solar system
Based on their location in the Periodic Table, which of the following pairs of elements would react with water in a similar way because they are in the same group and family?
A) Na, CI
B) Si, As
C) K, Rb
D) Cs, Ba
A one paragraph summary of 5 sentences of how petroleum forms. Which must include the following terms:
-Sea
-organisms
-pressure
-high temperatures
-petroleum
-sediments
-sedimentary rock
-seafloor
-millions of years
please underline the words I just showed: pays 30
Petroleum is a fossil fuel that was formed from sediments of plants and animals left over millions of years through the transformation of dead organisms that are buried under the sea and seafloors such as algae, plants, and bacteria, that experienced high temperature and pressure when trapped inside rock formations such as the sedimentary rocks.
What is petroleum?Petroleum, also referred to as crude oil, is a naturally occurring liquid found beneath the earth’s surface which can be refined into fuel.
Petroleum is a fossil fuel that is created by the decomposition of organic matter over time and used as fuel to power vehicles, heating units, and machines, and can be converted into plastics.
Petroleum is mostly recovered through oil drilling and then refined and separated into different types of fuels. Petroleum contains hydrocarbons of different molecular weights. The petroleum has a property of the denser the petroleum the more difficult it is to process and the less valuable it is.
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2. A 1kg book falls on the floor when sitting at the height of 4m how much kinetic energy
does the book have?
The object's potential energy is highest at the height from which it is dropped. Its potential energy diminishes while its kinetic energy grows as it descends.
PE = 1 kg
g = 9.8 m/s2
h = 100 m PE =? J m
PE = 1 kg 9.8 m/s2 = 980 kg•m2/s2 = 980 J
Is kinetic energy affected by height?In contrast to potential energy, an object's kinetic energy is related to other fixed and moving objects in its immediate environment. For example, if the object is positioned at a larger height, its kinetic energy will be greater.
According to its mass and beginning height, an item carried at a specific height above the ground has an initial potential energy (PE). When the thing is released, the velocity of the object rises as it falls. This increase in velocity increases the object's kinetic energy (KE).
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A student adds 10 ice cubes to a large beaker filled with 400 mL of water. Which of the following
best describes the contents of the beaker?
A pure substance
B heterogeneous mixture of a pure substance
C homogeneous solution of two substances
D solution of two pure substances
Ответ:ответ
.Объяснение:т.к вода это одно вещество и лёд тоже делают из
A compound of carbon and hydrogen and oxygen (ethylene glycol- antifreeze) is determined to be 38. 7% C, 51. 6% O, and 9. 7% H. Calculate the molecular formula of the molar mass is 62 g/mol
The molecular formula of the given is 0.519.
Equation :To calculate the molecular formula we need a simple formula,
molecular formula = divide the molecular mass / empirical formula
So, the known are
molecular mass = 62 g/mol
empirical formula = CH₃O
C = 38. 7%
H = 9. 7%
O = 51. 6%
empirical formula = 38. 7% + (9. 7% x 3) + 51. 6%
empirical formula = 119.4
Now, putting the values in formula
molecular formula = molecular mass / empirical formula
molecular formula = 62 g/mol / 119.4
molecular formula = 0.519
Hence, the molecular formula is 0.519.
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Help me i have till 5 to get this assignment in
Energies of given waves exists:
6. 17.27 × [tex]10^{-20}[/tex] J
7. 63.61 × [tex]10^{-23[/tex] J
8. 9.99 × [tex]10^{-24}[/tex] J
9. 41.5 × [tex]10^{-21}[/tex] J
10. 16.89 × [tex]10^{-19}[/tex] J
What is the relation of frequency and energy?E = hv is the energy equation. In the formula, E stands for energy, h for Planck's constant (6.626 × 10 -34 J s), and v for frequency. Since frequency rises as energy falls, frequency and energy are related directly in the energy equation.Energy travels in waves. Their frequency and amplitude both affect how much energy they transport. The amount of energy increases with frequency and amplitude, respectively.Energy is inversely correlated with wavelength because it is directly proportional to the electromagnetic frequency of the photon. The energy of a photon increases with its frequency. In other words, the energy of a photon decreases with increasing wavelength.The energies of given waves exists:
6. 17.27 × [tex]10^{-20}[/tex] J
7. 63.61 × [tex]10^{-23[/tex] J
8. 9.99 × [tex]10^{-24}[/tex] J
9. 41.5 × [tex]10^{-21}[/tex] J
10. 16.89 × [tex]10^{-19}[/tex] J
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for the reaction co(g) h2o(g) <--> co2(g) h2(g) calculate the equilibrium concentrations of all species if 1.000 mol of each reactant is mixed in a 1.000l flask. kc
The equilibrium concentration [tex]k_{c}[/tex] = 0.57.
What is equilibrium concentration?Equilibrium is when the rate of the forward reaction equals the rate of the reverse reaction. All reactant and product concentrations are constant at equilibrium.
Given reaction:
co(g) + [tex]H_{2}o[/tex] <--> [tex]co_{2}[/tex](g) + [tex]H_{2}[/tex](g)
co = 1 mole
[tex]H_{2}o[/tex] = 1 mole
[tex]H_{2}[/tex] = 0.43 mole
Each reactant is mixed in a 1 liter flask.
equilibrium concentration = ?
Equilibrium amount:
co = 1 - 0.43 = 0.57 mole
[tex]H_{2}o[/tex] = 1 - 0.43 = 0.57 mole
[tex]co_{2}[/tex] = 0 + 0.43 = 0.43 mole
[tex]H_{2}[/tex] = 0 + 0.43 = 0.43 mole
Then, equilibrium concentration
co = 0.57/1 liter = 0.57 mole
[tex]H_{2}o[/tex] = 0.57/1 lite r= 0.57 mole
[tex]co_{2}[/tex] = 0.43/1 liter= 0.43 mole
[tex]H_{2}[/tex] = 0.57/1 liter = 0.57 mole
[tex]k_{c} = \frac{[H_{2} ][co_{2} ]}{[H_{2}0 ][co]}[/tex]
[tex]K_{c} = \frac{0.43.0.43}{0.57.0.57}[/tex]
[tex]k_{c}[/tex] = 0.57
Hence, The equilibrium concentration [tex]k_{c}[/tex] = 0.57.
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In the common naming convention for carboxylic acids, what is the correct greek letter used for the carbon adjacent to the carboxyl group?.
The correct Greek letter used for the carbon adjacent to carboxyl group is alpha (α).
What is carboxylic acid?
Any of a group of organic compounds known as carboxylic acids in which a carbon (C) atom forms a double bond with an oxygen (O) atom and a single bond with a hydroxyl group (OH). The carbon atom is connected to a hydrogen (H) atom or another univalent combining group by a fourth bond. The carbonyl group (C=O) and hydroxyl group are what give the carboxyl (COOH) group its name. The acidity of the carboxylic acids is one‘s primary chemical characteristic. They are typically weaker than the well-known mineral acids but generally more acidic than other organic compounds with hydroxyl groups (e.g., hydrochloric acid, HCl, sulfuric acid, H2SO4, etc.).
Greek letter used for the carbon adjacent to the carboxyl group is Alpha.
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Potassium is an element in group 1 of the periodic table and so it forms __________ ions. Give one word, not symbols or numbers.
Potassium is an element in group 1 of the periodic table and so it forms positive ions
A Potassium atom acquires a charge of +1 to enter its noble gas electron configuration that's why it is found in group 1 of the periodic table of the elements and it is called as K⁺ ion and K⁺ ions have 1 less electron than K atoms
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Almost all of an atom's mass is found in its nucleus, located in the center of the atom. An atom's nucleus can contain two types of particles: protons and neutrons. The nucleus of every atom contains one or more protons. Each proton has a positive electrical charge. In many atoms, the nucleus also contains neutrons. A neutron has no electrical charge. Determine whether each statement is true or false to complete the table.
Almost all of an atom's mass is found in its nucleus, located in the center of the atom an atom's nucleus can contain two types of particles: protons and neutrons the nucleus of every atom contains one or more protons each proton has a positive electrical charge. In many atoms, the nucleus also contains neutrons a neutron has no electrical charge all the statements are true
Protons are positively charged, neutrons are uncharged and electrons are negatively charged the negative charge of one electron balances the positive charge of one proton and both protons and neutrons have a mass of 1, while electrons have almost no mass
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I just did it in IXL
When a screen is used to easily separate substances, what physical properties are being used?
Responses
temperature, size
temperature, size
size, shape
size, shape
texture, shape
texture, shape
density, buoyancy btw this is science
When a screen is used to easily separate substances, what physical properties are being used then the size are used
A physical property is a characteristic of matter that is not associated with a change in its chemical composition and similar examples of physical properties include density, color, hardness, melting and boiling points, and electrical conductivity and the physical property that is in use when substances are separated using a screen is differences in particle size of the substances and this is the separation method
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Answer:
d
Explanation:
A typical car battery in a car is filled with a solution of sulferic acid, which is approximately 39.9% sulfuric acid. If the density of this
solution is 1.3 g/mL, determine the number of grams present in 500.0mL of battery solution.
This tells you that the reaction will always consume 2 times more moles of lithium hydroxide than moles of sulfuric acid.
Explanation of Sulfuric Acid?The balanced chemical equation can be used to help you figure out how many moles of each reactant must be present in solution in order for complete neutralization to occur when it comes to neutralization reactionH2SO4(aq]+ 2LiOH(aq]→ Li2SO4(aq]+ 2H2O(l]Lithium hydroxide and sulfuric acid have a 2 mole ratio. You can infer from this that the reaction will always consume.Lithium hydroxide has twice the moles of sulfuric acid.
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The important discovery from Rutherford’s gold foil experiment was that _______________.
Group of answer choices
alpha particles pass through gold un-deflected because of the small size of the atom.
alpha particles are dense
electrons are not attracted to positively charged alpha particles.
the volume occupied by an atom is largely empty space.
The important discovery from Rutherford’s gold foil experiment was that the volume occupied by an atom is largely empty space.
What is an experiment?An experiment can be described as a procedure carried out to support or refute a hypothesis, or determine the efficacy or likelihood of something previously untried.
Rutherford's model was the first to introduce the concept of an atomic nucleus. This novel idea accounted for the sparse distribution of electric charges that was revealed in Rutherford's famous gold foil experiment.
Rutherford in his experiment shot a beam of alpha particles at a sheet of gold foil, where some of these particles were deflected.
That accounted for the theory that the volume occupied by an atom is largely empty space.
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21. Write a conclusion, using the fimulation and
graph. Use what you have learned in this activity to support the following two statemer
How the molecules in a solid, liquid and gas compare to each other.
How temperature relates to the kinetic energy of molecules.
The interatomic bond or interaction defines the real attraction or repulsion between the molecules in whatever state may the solid, liquid, or gas.
What is temperature and molecular interaction?
As we have already learned it a lot of times about temperature , it is the measure of degree of hotness or coldness.Temperature is the measure of the degree of hotness or coldness , whatever may the degree is.There are various units of temperature used like celsius, farhenhite etc.See the interaction inside the matter is not so critical , as in solid the interaction is tight , the molecules are close to each other.In liquids molecules are loosely interacted , and in the gas molecules are at the peak of repulsion.The temperature in the matter is directly related to kinetic energy, in the context that higher the temperature the higher the kinetic energy.To know more about temperature visit:
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What would happen if three types of water
are placed in the same container?
Please may someone help me with the bottom bit!
Precipitate definition (Entry 2 of 3) 1: a substance that has been physically or chemically isolated from a solution or suspension, typically in the form of an insoluble crystalline or amorphous solid. 2: a byproduct, outcome, or result of a procedure or action. adjective. precipitate.
What is an example of precipitate in chemistry?Precipitation Illustration
Silver chloride will solidify out of solution when silver nitrate and sodium chloride are combined in water. Silver chloride is the precipitate in this instance.
What does precipitate represent?Solids are created by the process of precipitation after two chemicals react. The downword () arrow symbol is used to represent the production of precipitate in this type of reaction.
What two types of precipitate are there?It happens between the reactant ions in the aqueous solutions that give rise to the material. Complete response: Precipitation includes the following: snow, sleet, hail, and rain.
What color is precipitate?An excess of the light blue precipitate dissolves to create an inky transparent solution. A little amount of sodium hydroxide solution and subsequently an excessive amount are added to solution W. There develops an insoluble white precipitate.
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Zinc metal reacts with yellow crystals of sulfur in a fiery reaction to produce a white powder of zine sulfide. A chemist determines that 65.4 g zinc reacts with 32.1 g of sulfur. How many grams of zinc sulfide are produced?
Answer:
Explanation:
Zn + S ---> ZnS
Mass of Zinc + Mass of Sulphur = Mass of Zinc sulfide ( Law of conservation)
Mass of zinc= 65.4g
Mass of Sulfur = 32.1g
Mass of Zinc Sulfide= (65.4 + 32.1)g
Mass of Zinc Sulfide = 97.5g
Please help as much as you can!! Most accurate answer will get brainlist and my heart
Based on the graph of mass against volume;
1. the mass of a sample of galena would be 22.5 g if it has a volume of 3.0 cm³
2. the volume of a sample of galena would be 4.00 cm³ if it has a mass of 30.0 g
3. the relationship between the mass and volume as shown by the graph is that the mass of the galena sample is directly proportional to the volume of the sample.
4. the density of Sample 2 compared to that of Sample 4 is the same.
5. the density of the largest sample (5) compare to the smallest sample (1) is the same.
6. the effect of sample size on the density of a material is that the density of a sample is independent of the mass.
What is the relationship between the mass and volume of a sample of known density?The mass and the volume of a sample of known density are directly proportional.
This means that the mass increases with the volume and vice versa.
Considering the given graph, the density of the galena sample is constant ad the volume increases as the mass increases.
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an approximate partition function for a dense gas is given by where and are constants that are independently determined from molecular parameters. calculate (a) the thermal equation of state, (b) the energy , and (c) constant volume specific heat for this gas. d) finally, show that (these results correspond to the van der waals equation of state which approximates effects due to intermolecular interactions) .
As the values of these constants become closer to zero, the ideal gas law PV=nRT and the van der Waals equation of state get closer. For the intermolecular forces, the constant a serves as a correction. The value of constant b, which corrects for finite molecular size, is the volume of one mole of atoms or molecules.
The perfect gas equation, P = RT, is the most often used thermal equation of state. The fact that all gases can be liquefied serves as the finest illustration of its limitation for genuine fluids. The fluid's critical point is determined by the greatest temperature at which liquid and vapour may coexist.
The state equation for a van der Waal's gas is (P+n2aV2)(Vnb)=nRT. U=CTn2aV describes the internal energy's variation.
Since the pressure is predicted to be a linear function of temperature by the van der Waals equation, (CV / V)T = 0 and CV is independent of gas volume. Because the van der Waals gas acts like an ideal gas at very high volumes, its heat capacity is equivalent to that of an ideal gas.
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Circle the correct word: Protons and neutrons contribute (mass or volume) to the atom.
Answer:
mass
Explanation:
Protons and neutrons contribute mass to the atom.
heat is added to a 200.-gram sample of h2o(s) to melt the sample at 0°c. then the resulting h2o( ) is heated to a final temperature of 65°c. 5. compare the amount of heat required to vaporize a 200.-gram sample of h20( ) at its boiling point to the amount of heat required to melt a 200.-gram sample of h2o(s) at its melting point.
54.418 kJ amount of heat required to completely melt the200gm of H2O sample at its melting point.
What is the calculation of the above problem?Mass of water = 200 g
Initial temperature of the water = 0°C
Final temperature of the water = 65°C
Temperature change = Delta T = 65
Specific heat capacity = 4.168J/g C
(1 kJ = 1000J)
54.418 kJ amount of heat required to completely melt the sample.
At 100 C and 1 atm, how much heat is required for 1 g of water to evaporate?At 100 °C, which is where water boils, the heat of vaporization for water is around 540 cal/g.
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In each pair below, circle the particle which you believe is larger and justify your choice in the space
provided.
Lithium Atom or Lithium Common Ion
Fluorine Atom or Fluorine Common Ion
Sodium Common lon or Magnesium Common Ion
Oxide Common lon or
Fluoride Common lon
Lithium Atom, Fluorine common ion, Magnesium Common ion, Oxide common ion are the ones that are larger in each of the choices as given.
What are cations and anions?Positively charged ions are known as cations. Negatively charged ions are further referred to as anions. A charged atom or molecule can be referred to as an ion.
A balanced atom will change into a positively charged cation if one or more of its electrons are lost. A balanced atom will change into a negatively charged anion if it gains one or more electrons.
In the formula for an ionic compound, the positive ion, known as a cation, is listed first, followed by the negative ion, known as an anion. The net charge or neutral electrical charge in a balanced formula is zero. A cation can be either positive or negative.
An anion contains more protons than electrons, while a cation has a net positive electrical charge. An anion has a greater number of electrons than protons and a net negative electrical charge.
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pentacarbonyliron (fe(co)5) reacts with phosphorous trifluoride (pf3) and hydrogen, releasing carbon monoxide: fe(co)5 2pf3 h2 → fe(co)2(pf3)2(h)2 3co the reaction of 5.0 mol of fe(co)5, 8.0 mol of pf3 and 6.0 mol of h2 will release mol of co.
Fe(CO)₅ is the limiting reactant given the provided statement since it has the lowest ratio.
What defines a limiting reactant?The quantity of product that can be created is constrained by the reagent that is used first in a chemical reaction, also referred to as the limiting reactant (or limiting reagent).
Briefing:Calculating the moles supplied/moles stoich ratio will reveal the limiting reactant, which is the one with the lowest value.
Fe(CO)₅ ratio = [5 g / 195.9 g/mol] / 1
Fe(CO)⁵ ratio = 0.025
PF3 ratio = [8 g / 87.97 g/mol] / 2
PF3 ratio = 0.045
H2 ratio = [6 g / 2 g/mol] / 1
H2 ratio = 3
We can see that Fe(CO)5 has the lowest ratio, so it is the limiting reactant.
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what effect does a catalyst have on the energy of a reaction system
Which sample is composed of particles arranged in a regular geometric pattern?
A) Cl2(g)
B)CCl4(l)
C)LiCl(s)
D)LiCl(aq)
Solid Lithium chloride (LiCl) is made up of particles arranged in a regular geometric pattern. Therefore, option (C) is correct.
What types of solids have geometric patterns?In the crystalline Solid, the constituent particles are closer to each other due to the intermolecular force of attraction between them. So there is no free space between them due to which its shape can't be changed which is said to be regular geometry.
The building constituents in crystalline solids, arrange in a regular manner throughout the entire 3D network. The ordered arrangement of constituent units extends over a large distance. Thus, crystalline solids have a long-range arrangement. A crystalline solid contains a large number of units called crystals.
Lithium Chloride is a white solid soluble in water, ether, and alcohol and chemical formula for lithium chloride is LiCl. Lithium chloride has the same crystal structure as NaCl.
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what is the formula for aqueous sodium hydrogen carbonate reactions with aquesous acetic acid to form liquid water, gaseous cabon dixoide and aqueous sodium acetate metal reacts with solid iron(lll) oxide to form solid iron and solid aluminum oxidexide with aqueous magnesium chloride to form soild magnesium hydroxide snf potassium chloride
The balanced reaction equations for the described reactions are given below. The first reaction is a combination of a double displacement and a decomposition reaction, the second one represents single displacement reactions, and the third one is multiple double displacements.
The balanced reaction equation (including a double displacement and a decomposition) between aqueous sodium hydrogen carbonate and aqueous acetic acid (resulting in the formation of liquid water, gaseous carbon dioxide, and aqueous sodium acetate) looks like this:
NaHCO₃(aq) + AcOH(aq) → CO₂(g) + H₂O(l) + NaOAc(aq)
The balanced reaction equation between aluminum metal and iron(III) oxide (resulting in the formation of iron metal and aluminum oxide) looks like this:
2Al(s) + Fe₂O₃(s) → 2Fe(s) + Al₂O₃(s)
The balanced reaction equation between solid potassium oxide with aqueous magnesium chloride (resulting in the formation of solid magnesium hydroxide and aqueous potassium chloride) looks like this:
K₂O(s) + H₂O(l) + MgCl₂(aq) → Mg(OH)₂(s) + 2KCl(aq)
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