A Biotechnologist decides to use directed evolution as an enzyme engineering technique when the enzyme mechanisms is understood and provides insight to engineering Why is directed evolution important?
A potent method for enhancing the functionality of proteins is directed evolution. When the biological function is unclear or there is little chemical understanding of the substrate and protein structure, directed evolution generates hundreds of variants in order to find the optimal solution.
What is enzyme engineering technique?
In order to increase the usefulness and activity of existing enzymes, enzyme engineering approaches use recombinant DNA technology to develop new proteins and enzymes with designer functions.
What is rational design?
In synthetic science and biomolecular designing, sane plan (RD) is an umbrella term which welcomes the system of making new particles with a specific usefulness, in light of the capacity to foresee how the atom's construction (explicitly got from themes) will influence its conduct through actual models.
Hence, Biotechnologist most likely to decide to use directed evolution as an enzyme engineering technique as opposed to rational design when the enzyme mechanism is understood and provides insight to engineering .
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Please help I have been stuck for a week Which of the following reactions is BALANCED and shows INCOMPLETE combustion
A. 2C5H12 + 1102--> 12CO+ 10H2O
B. 2C5H12 + 1102--> 10CO +12H20
C. C5H12 + 802--> 5CO2+6H20
D. C5H12 + 802--> 6CO2 5H20
The reaction that is balanced and shows incomplete combustion is:
2 C₅H₁₂ + 11 O₂--> 10 CO + 12 H₂0; option B.
What is a combustion reaction?A combustion reaction is a reaction in which a substance reacts with oxygen to release large amounts of heat and light energy.
In the combustion of carbon-containing compounds, carbon dioxide and water are usually produced.
In incomplete combustion of carbon compounds, carbon monoxide or carbon (ii) oxide is produced.
For a balanced reaction, the moles of atoms of elements on the reactant side are equal to the moles of atoms on the product side.
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the number of electron dense areas of SeCl6
Using the Valence shell electron pair repulsion theory, there are six electron dense areas in the compound.
What is the valence shell electron pair repulsion theory?According to the valence shell electron pair repulsion theory, the number of electron pairs that surround the valence shell of the central atom of the molecule is the determinant factor of the shape of the molecule.
Thus, the repulsion between the electron pairs would make the compound to assume a certain shape as the electrons would be able to maximize the repulsion that does exists between them.
In this case, we have a compound that have a central tom that is surround be six electron pairs that surround the central atom and they are all bond pairs of electron thus we would have six areas of electron density.
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Consider the reaction: A+B---->2C. If 0.80 moles of C are formed, how many moles of A have been consumed by the reaction?
Answer:
0.40 mole of A
Explanation:
1 mole of A to produce 2 moles of C
so the number of mole of A to produce 0.80 mole of C is:
(0.80 x 1)/(2) = 0.40 mole
The gas tank of car hold 22.3 gallons.If the density of gasoline is 0.8206g/mL,determine the massin kilograms and pounds of the fuelin a full truck
Density = mass/Volume or D = m/V
Given: V = 22.3 gal
D = 0.8206 g/mL
1) Rearrange the equation to solve for m
2) Find conversion factor(s) and convert V from gal to mL (by dimensional analysis) so the units cancel
3) Solve for m in g
4) Find conversion factor(s) and convert m from g → lbs
1) D = m/V rearranges to m = D ∗ V
2) 1 gal = 3.785 L and 1 L = 1000 mL; 22.3 gal ∗ 3.785 L/1 gal ∗ 1000 mL/1 L = 84 406 mL
3) m = 0.8206 g/mL ∗ 84 406 mL = 69 260 g
4) 1 lb = 453.6 g; 69 260 g ∗ 1 lb/453.6 g = 153 lbs
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Read the chemical equation shown.
3SO2 + 2HNO3 + 2H₂O → 3H₂SO4 + 2NO
Which statement is true about this chemical equation?
OH (hydrogen) was oxidized and S (sulfur) was reduced.
OH (hydrogen) was reduced and N (nitrogen) was oxidized.
OS (sulfur) was oxidized and N (nitrogen) was reduced.
OS (sulfur) was reduced and N (nitrogen) was oxidized.
The statement "OH (hydrogen) was oxidized and S (sulfur) was reduced" is true about this chemical equation.
This chemical reaction is between Sulfur dioxide and nitric acid along with water. When nitric acid reacts with Sulfur dioxide, it gives sulfuric acid and nitrogen monoxide.
In the reaction, the hydrogen atoms in H₂O are oxidized to form H₂SO₄, and the sulfur atoms in SO₂ are reduced to form H₂SO₄.
Therefore, the OH from the water molecule gets oxidized to give out Sulfuric acid. Likewise, the Sulfur from Sulfur dioxide reduces to form the product that is sulfuric acid.
Therefore, the best option that suits the reaction is OH (hydrogen) was oxidized and S (sulfur) was reduced.
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Answer:
I believe the above answer is correct after my test i will let everyone know.
Explanation:
What is the pH of a solution prepared by adding 25.0 mL of 0.199 M ammonia to 25 mL of 0.199 M hydrochloric acid solution?
The pH of a solution prepared by adding 25.0 mL of 0.199 M ammonia to 25 mL of 0.199 M hydrochloric acid solution is less than 7.
What is the pH of a solution?The pH of a solution is calculated as follows;
pH = - log ([H⁺])
Also, pH = 14 - pOH
The pH of the solution is determined as follows;
Moles of HCl = 0.199 M * 25 mL * 1L/1000 mL
moles of acid = 0.004975 moles
Moles of NH₃ = 0.199 M * 25 mL * 1L/1000 mL
moles of NH₃ = 0.004975 moles
0.004975 moles of HCl reacts with 0.004975 moles of NH₃
Since NH₃ is a weak acid, the pH of the solution is slightly lower than 7.
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A local AM radio station broadcasts at a frequency of 587 kHz.
Calculate the wavelength at which it is broadcasting.
Wavelength =
Explanation:
c=v * lambada
lambda= 3*10power of 8m/s ÷587×10power of 3 hzAre there any concerns if you wait an hour or two after you calibrate the spectrophotometer to obtain the absorbance of your solutions and unknown? Explain your answer.
No, there are no concerns if you wait an hour or two after you calibrate the spectrophotometer to obtain the absorbance of your solutions and unknown as it will not change because the light source is not aging faster but if your light source age faster, then there are concerns.
Why should it be a problem when the light source is aging faster?In the case above, light source is the issue because it is deteriorating quickly. If you're lucky, the lamp's usable life will be at least four digits of hours. On the other hand, allowing the lamp to stabilize itself speeds up aging. Given the limited lifespan, it is advisable to calibrate frequently such as daily.
The calibration rate is determined by the goal of the measurement. For most photometric tests, parameter variations in the interval between calibration and measurement will be negligibly large enough to significantly increase the overall measurement error. (Take note that the amount of error in typical analytical measurements, including sample preparation, is often at or above 10%.)
The routine calibration then appears to be unnecessary because the effort you put out will be pointless. In any instance, the experimental analysis of the impact of daily or biweekly calibration (often conducted inside validation studies) will offer the response.
It may even make sense to calibrate the instrument every 5 or 10 operational hours if you are using it continuously for a long length of time. If the manufacturer changes the cuvette materials (they will also change the Lot No.), you should recalibrate depending on the light source's lifespan and the materials you used to place your samples there. however, you should be cautious of dust because it might significantly alter the outcomes if the lenses have dirt.
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How much water will be needed to make a solution of 5.0 M MgO with 200.0 g MgO?
Volume of water will be needed to make a solution of 5.0 M MgO with 200 g MgO is 25 L.
given that :
molarity of MgO = 5 M
mass of MgO = 200 g
molar mass of MgO = 40 g/mol
number of moles = mass / molar mass
number of moles of MgO = 200 g / 40 g/mol
= 5 mol
molarity of solution is given as :
molarity = moles of solute / volumes in L
volume = moles / molarity
volume = 5 × 5
= 25 L
Thus, Volume of water will be needed to make a solution of 5.0 M MgO with 200 g MgO is 25 L.
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A local AM radio station broadcasts at a frequency of 587 kHz. ()
Calculate the energy of the frequency at which it is broadcasting.
Energy =
kJ/photon
Explanation:
E=hv
6.626*10power of -34 * 587khz
What is the condensed structural formula for 2,2-dimethylbutane?
CH3(CH2)2CH3
(CH3)3CCH2CH3
C6H4(CH3)2
CH3CH2CH2CH2CH3
The structural formula for 2,2-dimethylbutane in the above task is (CH3)3CCH2CH3.
The correct answer choice is option b.
The structural formula for 2,2-dimethylbutane.It follows that the structural formula for the above compound in the above task has 4 carbon atoms as the parent chain and has 2 different methyl substituents on the same carbon 2.
The image to the paper work is attached for more clearity.
The compound; 2,2-dimethylbutane ( (CH3)3CCH2CH3 ) belong to an alkane family. They have a general formula CnH2n+2.
So therefore, we can now confirm from the explanation given above that the only correct answer for the structural formula of the compound above is (CH3)3CCH2CH3
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15. A 100 g sample of each of the following metals is heated from 35°C to 45°C. Which metal absorbs
the greatest amount of heat energy?
Metal
4
magnesium
e. copper
copper
magnesium
mercury
silver
lead
b. lead
c. silver
Specific Heat Capacity
0.385 J/(g-°C)
1.02 J/(g-°C)
0.138 J/g °C)
0.237 J/(g-°C)
0.129 J/(g-°C)
d. mercury
The metal that absorbs the greatest amount of heat energy is lead.
Heat energy is the result of the movement of tiny particles called atoms, molecules liquids and gases. Heat energy can be transferred from one object to another. The transfer or flow due to the difference in temperature between the two objects is called heat.
The equation that relates the specific heat capacity to the heat absorbed by the metal is given by:
q= m[tex]C_{p}[/tex]ΔT where q = heat absorbed by the the metal, m = mass of the metal, [tex]C_{p}[/tex] = heat capacity of the metal and ΔT is the change in temperature
In the above given question, the mass of the metal and change in the temperature is the same for all the metals. Therefore, we can determine the metal that will absorb the lowest amount of energy by using the specific heat capacity.
From the equation the heat absorbed by the metal (q) is directly proportional to the specific heat ([tex]C_{p}[/tex]). Hence we can see that lead has the highest specific heat capacity and therefor Lead absorbs the maximum amount of heat.
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What is the physical state of caesium at 25 degrees?
Answer:
298k
Explanation:
because 298k is lower than 302k
How many grams of propane can combust at 25°C and 1.04 atm if reacting with 14.7 L of oxygen gas?
The volume of oxygen is 14.7 litres.
What is volume?
volume is a measure of occupied three dimensional space.
Sol-Balanced chemical reaction: C₃H₈ + 5O₂ → 3CO₂ + 4H₂O.
m(C₃H₈-propane) = 5.53 g.
n(C₃H₈) = m(C₃H₈) ÷ M(C₃H₈).
n(C₃H₈) = 5.53 g ÷ 44.1 g/mol.
n(C₃H₈) = 0.125 mol.
From chemical reaction: n(C₃H₈) : n(O₂) = 1 : 5.
n(O₂) = 0.625 mol.
T = 25° = 298.15K.
p = 1.04 atm.
R = 0.08206 L·atm/mol·K.
Ideal gas law: p·V = n·R·T .
V(O₂) = n·R·T / p.
V(O₂) = 0.625 mol · 0.08206 L·atm/mol·K · 298.15 K / 1.04 atm.
V(O₂) = 14.7 L.
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2. If a solid dissolves in the liquid, sedimentation and decantation method cannot be used.Why?
Answer:
The answer is if a solid gets dissolved in a liquid then sedimentation and decantation cannot be used because these methods are used to separate an insoluble solid substance but if we add a little sugar or salt it will dissolve in the liquids it is soluble solid making it hard to separate.
Explanation:
I hope this helps
covert 3.20 bar to atm
Taking into account the change of units, the 3.20 bar in atm is 3.15815 atm.
Rule of threeThe rule of three is a way of solving problems of proportionality between three known values and an unknown value, establishing a relationship of proportionality between all of them.
If the relationship between the magnitudes is direct, the direct rule of three must be applied. To solve a direct rule of three, the following expression must be followed, being a, b and c known data and x the variable to be calculated:
a ⇒ b
c ⇒ x
So: x= (c×b)÷a
The direct rule of three is the rule applied in this case where there is a change of units.
Conversion of units in this caseYou can apply the following rule of three: if 1.01325 bar equals 1 atm, 3.20 bar equals how many atm?
1.01325 bar ⇒ 1 atm
3.20 bar ⇒ x
So: x= (3.20 bar× 1 atm)÷ 1.01325 bar
Solving:
x= 3.15815 atm
In summary, the pressure is 3.15815 atm.
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Each element is composed of a unique kind of atom.
True or False
Answer:
True.
Explanation:
Write the net ionic equation for this reaction Fe₂(SO4)3²(aq)+3K₂S(aq) → Fе₂S3(s)+3 K₂SO4(aq)
A known reaction has Change in U= 38 kJ/mol. The reaction is done at constant pressure and you measure the amount
of work done to be w=+2 kJ/mol. What is q in kJ/mol?
q = 36kJ/ mol amount of heat is produced according to 1st law of Thermodynamics
What is 1st law of Thermodynamics ?
The first law of thermodynamics states that energy is neither created nor destroyed, only its form can be changed. In any system, energy transfer involves exceeding control limits by mass, external work, or heat transfer beyond limits. These cause changes in the stored energy within the control volume.
The first law of thermodynamics states that heat is a form of energy and therefore thermodynamic processes obey the law of conservation of energy. This means that it cannot generate or destroy thermal energy.
ΔU = q + w
38kJ/ mol = q + 2kJ/mol = 36kJ/mol
q = 36kJ/ mol amount of heat is produced according to 1st law of Thermodynamics
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Will three different liquids lose heat at the same rate?
Yes, because of the liquid's specific heat capacity or heat capacity, different liquids heat up at varying speeds.
What does the same quantity of heat gain or lose at the same temperature?Which amount of heat is needed to raise the liquid's temperature by one degree Celsius? When analyzing a mass of 1 kg, the term "heat capacity" or "specific heat capacity" refers to the amount of heat needed to raise the temperature of 1 kilogram of liquid or fluid by 1°C.
What aspects of a liquid's rate of heat loss are there?area of the body's surface. nature of the body's surface. the body's surface's composition (material effects conductivity through walls of the body).
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how did the scientist explain the relationship beetween the colors observed and the structure of the atom
Answer:
The colors observed is a sign that definite energy transformations occurs inside the atom gives off light. It follows that electrons must occupy orbits of fixed energy.
Hope that helps!
How much heat is released during the combustion of 1.39 kg of C5H12?
The heat that is released by the 1.39 Kg of pentane is 58518 kJ.
What is the heat released?We know that the combustion of pentane is an exothermic reaction because heat is released in the process. We have to look to the balanced thermochemical reaction equation for the combustion of pentane.
Given that the number of moles of the pentane that is burnt here = 1.39 * 10^3 g/72 g/mol
= 19.3 moles
Now;
If we require 3032 kJ of energy to burn one mole of pentane
If we have 19.3 moles of pentane then we have;
19.3 moles * 3032 kJ/ 1 mole
= 58518 kJ
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I really need help!
I promise I've been paying attention, it just goes in one ear and out the other ;-;
(question is in picture!)
Answer: the balanced equation is the same.
Explanation:
Every element must have the same number of atoms on each side of the equation (law of conservation of mass).
2. Balancing the equation can be done only by adjusting the coefficients.
C
is a balanced element because there is the same number of atoms of
C
in each side of the equation.
C
is a balanced element
H
is a balanced element because there is the same number of atoms of
H
in each side of the equation.
H
is a balanced element
O
is a balanced element because there is the same number of atoms of
O
in each side of the equation. O is a balanced element. Na is a balanced element because there is the same number of atoms of Na on each side of the equation. Na is a balanced element H is a balanced element because there is the same number of atoms of H on each side of the equation. H is a balanced element C is a balanced element because there is the same number of atoms on each side of the equation. C is a balanced element. O
is a balanced element because there is the same number of atoms of
O in each side of the equation. O is a balanced element. All elements have the same number of atoms on each side of the equation, which means that the law of conservation of mass is satisfied and thus the chemical equation is balanced.
Why do all elements have their own unique color? Please explain.
All the element have their own unique color because the every element have their own set of energy levels.
According to the bohr model of atoms : electrons exist at certain energy levels. when we give heat to electron , it gets excited and moves from lower energy level to higher energy level. the electron is less stable in higher energy level. when an electron returns from higher energy level to lower energy level it emits some energy in form of radiation. The wavelength of light depends upon energy level . and every elements have their own unique energy levels. The color for different element is different.
Thus, All the element have their own unique color because the every element have their own set of energy levels.
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Convert the boiling temperature of liquid ammonia, −28.1 °F, into degrees Celsius and Kelvin. Show the calculations.
-28.1 °F is a temperature in Fahrenheit and is converted to degrees Celsius and Kelvin as follows:
-33.39°C239.76KHow to convert Fahrenheit to Kelvins?Temperature is the measure of cold or heat, often measurable with a thermometer.
Temperature can be measured in the following units;
Kelvins (absolute temperature)
Degrees Celsius (°C)Degrees Fahrenheit (°F)Kelvins (K) is the international system of units (S.I unit), the base unit of thermodynamic temperature; 1⁄273 of the thermodynamic temperature of the triple point of water.
Degrees Celsius is the metric unit of temperature, a derived unit of the International System of Units.
°F is converted to °C as follows:
(32°F − 32) × 5/9 = 0°C
-28.1°F = -33.39°C
°F is converted to K as follows:
(-28.1°F − 32) × 5/9 + 273.15 = 239.761K
= 239.76K
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Please Help Me I don't Understand It.
Answer:
Javier's model is better, as the ball-and-stick model shows distinct differences in bond, whereas Carlos' model just shows them as differently colored circles.
Copper metal plus zinc sulfate solution
Write the Molecular equation
Write the total ionic equation
Write the Net ionic equation
Is the reaction category replacement or metathesis?
Copper metal plus zinc sulfate solution : is not possible because the copper metal is less reactive than zinc and copper cannot displace the zinc.
The copper metal with zinc sulfate reaction is not possible because copper is less reactive than the zinc cant cannot displace the zinc. so, the reaction :
Cu + ZnSO₄ ----> no reaction
but the zinc plus copper sulfate is possible , copper is less reactive than zinc and zinc can displace the copper . and the reaction is called as displacement reaction the reacion is given as :
CuSO₄ + Zn -----> ZnSO₄ + Cu
Thus, Copper metal plus zinc sulfate solution : is not possible because the copper metal is less reactive than zinc and copper cannot displace the zinc.
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Which process uses the most water in the United States?
public use
irrigation
industry
power plants
The most water in the United States is used power plants (thermoelectric power)
What are thermoelectric power plants ?
Water flowing through the boiler's network of pipes is heated, turning it into steam. A shaft connecting a turbine to a generator rotates the blades of a turbine powered by high-pressure steam. As the generator turns, electricity is generated. The thermoelectric power of a given metal is that of a couple made of that metal with lead, with the thermoelectric power of lead being arbitrarily regarded as zero. Rate of change of the thermoelectromotive force of a thermocouple with temperature.
Industrial water withdrawals make up just 5% of all water withdrawals in the US, but thermoelectric power draws make up 49% of all withdrawals. About 12% of the public water supply is also used by industrial and manufacturing companies.
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A 98.3 g piece of copper (specific heat 0.380 J/g・°C) is heated and then placed into 400.0 g of water initially at 20.7°C. The water increases in temperature to 22.2°C. What is the initial temperature (in °C) of the copper? (The specific heat of water is 4.184 J/g・°C)
The initial temperature of copper is 89.41°C.
How to calculate temperature?Calorimetry is the science of measuring the heat absorbed or evolved during the course of a chemical reaction or change of state.
According to this question, a 98.3 g piece of copper with specific heat of 0.380 J/g・°C is heated and then placed into 400.0 g of water initially at 20.7°C. The water increases in temperature to 22.2°C. The initial temperature can be calculated as follows;
Q = mc∆T
Where;
Q = quantity of energym = mass of substancec = specific heat capacity∆T = change in temperatureQ(water) = -Q(metal)
400 × 4.184 × 1.5 = -(98.3 × 0.38 × {22.2 - x})
2510.4 = - (829.26 - 37.354x)
2510.4 = -829.26 + 37.354x
3339.659 = 37.354x
X = 89.41°C
Therefore, 89.41°C is the initial temperature of the copper metal.
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The initial temperature of the copper piece is approximately 0.72°C.
Explanation:
To find the initial temperature of the copper piece, we can use the equation Q = mcΔT, where Q is the heat energy, m is the mass of the substance, c is the specific heat capacity, and ΔT is the change in temperature.
First, let's calculate the heat energy gained by the water. The mass of the water is 400.0 g, and the change in temperature is 22.2°C - 20.7°C = 1.5°C.
Using the equation Q = mcΔT, we have:
Q_water = (400.0 g)(4.18 J/g • °C)(1.5°C) = 2490 J
Next, let's calculate the heat energy lost by the copper piece. The mass of the copper is 90.7 g, and the change in temperature is the same as the water, 1.5°C.
Using the equation Q = mcΔT, we have:
Q_copper = (90.7 g)(0.380 J/g • °C)(1.5°C) = 51.8 J
Since energy is conserved, the heat energy gained by the water is equal to the heat energy lost by the copper piece:
Q_water = Q_copper
2490 J = 51.8 J
Now, let's solve for the initial temperature of the copper piece. Rearranging the equation Q = mcΔT to solve for the initial temperature, we have:
T_initial = (Q_copper) / (m_copper * c_copper)
Substituting the values, we get:
T_initial = (51.8 J) / (90.7 g * 0.380 J/g • °C) ≈ 0.72°C
Therefore, the initial temperature of the copper piece is approximately 0.72°C.
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There are 0.05216 mol ZnSO4 and 0.3609 mol H2O in the sample. Step 3: Divide each by the smallest number of moles to get the ratio. What is the ratio of ZnSO4:H2O? [?] mol ZnSO4: [?] mol H2O
If there are 0.05216 mol of [tex]ZnSO_4[/tex] and 0.3609 mol of [tex]H_2O[/tex] in a hydrated salt sample. the ratio of [tex]ZnSO_4[/tex] and [tex]H_2O[/tex] would be 1:7.
Empirical formulaThe problem here can be solved using the empirical formula method. There are 0.05216 mol of [tex]ZnSO_4[/tex] and 0.3609 mol of [tex]H_2O[/tex]. In order to find the mole ratio of the 2 constituents, let's divide by the smallest mol:
The smallest mol here is the mol of [tex]ZnSO_4[/tex] which is 0.05216.
[tex]ZnSO_4[/tex] = 0.05216/0.05216
= 1
[tex]H_2O[/tex] = 0.3609/0.05216
= 7
Thus, the mole ratio of the two constituents is 7 and 1. The formula for the hydrated compound would be [tex]ZnSO_4[/tex].7[tex]H_2O[/tex].
In other words, 1 mol [tex]ZnSO_4[/tex]: 7 mol [tex]H_2O[/tex].
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