According to the given statement one mole of potassium has a mass of 39.1 g.
Briefing:Each element's atomic weight is listed in a periodic table along with how many grams (or an Avogadro number) are needed to make one mole of atoms. Since potassium has an atomic weight of 39.0983 g/mole, a mole of potassium weighs 39.1 g.
What is Avogadro's number explain?Avogadro's number, which is equal to 6.02214076 * 10²³, is the quantity of units in one mole of any material (defined as its molecular weight in grams). Depending on the substance and the nature of the reaction, the units could be electrons, atoms, ions, or molecules.
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Now that we have put a coefficient of 2 in front of Na3PO4 , what coefficient should go in front of NaCl to balance sodium ( Na )? 2Na3PO4+MgCl2→Mg3(PO4)2+?NaCl Express your answer numerically as an integer.
A coefficient of 2 has been put in front of Na₃PO₄, so to balance Na coefficient in front of NaCl will be 6.
The balanced equation of the reaction is -
2 Na₃PO₄ + 3 MgCl₂ → Mg₃(PO₄)₂ + 6 NaCl
This is a complete balance chemical equation of the given reaction with coefficient 6 in front of NaCl to balance Na.
Here,
We've been given a chemical equation which is unbalanced. A coefficient of 2 has been put in front of Na₃PO₄ and we are asked about what coefficient should go in front of NaCl so that the sodium Na is balanced. Since, there were total 3 Na before the coefficient was placed, but after putting the coefficient of 2, Na is 2 x 3, which is 6.
Therefore, an integer 6 is to be put in front of NaCl to balance Na in the equation.
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PLEASE HELP, WILL MARK BRANLIEST!!
The half-life of cobalt-60 is 10.47 min. How many grams of cobalt-60 remain after 104.7 min if you start with 1024g?
Answer: 1 gram
Explanation:
- the equation is 1024(.5)^10
• so 1024g is your initial amount and it’s the amount that is being decayed
• since it’s half-life, the decay factor is 0.5
• the half life is 10.47 minutes, so 10.47 minutes would be considered one round of half life.
-basically, if you were finding the half life after 10.47 minutes you would use the equation 1024(.5)^1.
-as said, it’s raised to the 1st power because 10.47 minutes is one round.
• since you’re looking for the amount after 104.7 minutes, the equation is raised to the 10th power because 104.7 / 10 = 10.47. so 104.7 is 10 rounds of half-life.
- so 1024(.5)^10 = 1
so the half-life of 1024g of Cobalt-60 after 104.7 minutes is 1
hope this helps :)
Which of the following formulas represent valid ionic compounds that can be made from these six elements: Al, Be, F, Li, N, and S? Select all that apply. A. AlN B. BeS C. AlLi D. LiF
The compound AlN, BeS, and LiF represents valid ionic compounds.
Ionic bonding:-
When all of the electrons are successfully transferred from one element to another, this sort of bonding is created. One element in this bonding is always a metal, whereas the other is invariably a non-metal.Thus, Al, Be, Li are metals and F, N, S are nonmetals which can form ionic bonding with each other. So, AlLi (Option C) rules out.Considering option A: - AlNThe valency of aluminum is 3 and nitrogen is of 3. The valency of the cations and the anions must be switched and subscripted in order to identify the ionic compound. Thus,Al N
3 3
Simplest ratio : - 1 1
AlN is an ionic compound and thus it is a valid ionic compound.The valency of beryllium is 2 and sulfur of 2. The valency of the cations and the anions are switched and put in subscripts to create the ionic compound. Thus,Be S
2 2
Simplest ratio : - 1 1
The ionic compound created is (b) BeS, making it a legitimate ionic compound.Fluorine and lithium both have valencies of 1. The valency of the cations and the anions are switched and put in subscripts to determine the ionic compound. Thus,Li F
1 1
The ionic compound created is (d) LiF, making it a legitimate ionic compound.To learn more about ionic compounds visit:
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NEVERMINDDDDDDDDDDDDDDD
Answer:
what is this free
branliest?
Terrance found a small hair on the victim’s shirt. What type of evidence does this BEST represent?
A.
trace evidence
B.
biological evidence
C.
ammunitions evidence
D.
impression evidence
Answer:
Biological evidence, since it was a hair, which forms part of the human
which of the following statements are consistent with dalton's atomic theory as it was originally stated?
a. Sulfur and oxygen atoms have the same mass.
b. All cobalt atoms are identical.
c. Potassium and chlorine atoms combine in a 1:1 ratio to form potass...
Option B. All cobalt atoms are identical and are consistent with dalton's atomic theory as it was originally stated.
The primary part of dalton's atomic theory states that everyone relies on is manufactured from atoms, which can be indivisible. the second part of the theory says all atoms of a given element are the same in mass and house. The 0.33 part says compounds are combos of two or more exceptional kinds of atoms.
Dalton's atomic theory, atoms of one element are all the equal or same. for this reason, the assertion that every cobalt atoms are identical is consistent with Dalton's concept of the shape of atoms.
Dalton's atomic concept additionally proposed that each atom of an element is identical in nature and exceptional elements vary in length, mass, and chemical properties. So, the accurate answer is choice 1 which says that the first and 2d statements are correct.
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If gas has a pressure of 536 and a volume of 645 liters and is 352 moles what is the new temp ?
To solve this question we have to use the ideal gas law:
[tex]PV=nRT[/tex]Where P is the pressure, V is the volume, n the number of moles, R the constant of ideal gases and T the temperature.
Solve the equation for T and replace for the given values. Remember that R has a value of 0.082atmL/molK:
[tex]\begin{gathered} T=\frac{PV}{nR} \\ T=\frac{536atm\cdot645L}{352mol\cdot\frac{0.082atmL}{molK}}=11977.54K \end{gathered}[/tex]According to this, the temperature of the gas is 11977.54K.
Define electronegativity.
A neutral atom has high electronegativity. Describe what happens to this atom during ionic bond formation.
No trolls, fake answers, copied answers
Electronegativity is defined as the ability of an element to accept electrons to its shell during a chemical reaction for the formation of a stable bond structure.
What is a neutral atom?A neutral atom is the atom that contains an equal amount of electrons and protons which means that is has a zero net charge. Example is sodium.
Electronegativity is defined as the ability of an element to accept electrons to its shell during a chemical reaction for the formation of a stable bond structure.
During ionic bond formation, the elements involved tries to obtain an octet structure by either donating or accepting electrons.
Alkali metals( such as the neutral element of sodium? have the lowest electronegativities, while halogens have the highest.
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I need help with filling out the cubes and emery’s, basically the Application: Assigning Oxidation numbers (shown in the photo)
According to the explanation about oxidizing and reducing agents from the previous session, we will find the answers to this question as well
Oxidation numbers are mostly found in previously made tables, there are plenty of tables where you can see the oxidation numbers for almost every element, a few rules to have in mind is H is usually +1, O is -2, Halogens are -1, group 1A metals are +1, transition metals are the ones that will shift a lot
1. Sn + 2 HCl -> SnCl2 + H2, this is the properly balanced equation
REACTANTS
Sn = 0, since it's a lone element in the reaction we assume its charge is 0 because is stable
H = +1
Cl = -1, it's a halogen
PRODUCTS
Sn = +2, we see now that Sn was oxidized and now has a positive charge
Cl = still -1
H2 = 0, was reduced, now with a 0 charge
2. 2 NaBr + Cl2 -> 2 NaCl + Br2
REACTANTS
Na = +1, metal from group 1A
Br = -1, halogen
Cl2 = 0 stable element
PRODUCTS
Na = +1
Cl = -1, it will be reduced
Br = 0, it will be oxidized
3. SiCl4 + 2 Mg -> 2 MgCl2 + Si
REACTANTS
Si = +4
Cl = -1
Mg = 0
PRODUCTS
Mg = +2, it will be oxidized
Cl = -1
Si = 0, it will be reduced
If I have 10.0g of Mg, what is my theoretical yield of MgCl2
Explanation:
First, let's write the balanced equation of formation of MgCl2 from Mg and Cl2:
Mg + Cl2 → MgCl2
Now let's transform 10.0g of Mg into moles, using the following formula: moles = mass/molar mass
molar mass of Mg = 24.3 g/mol
moles = 10/24.3
moles = 0.412 moles
Now we use the equation ratio between Mg and MgCl2 to find the quantity of MgCl2 in moles.
1 mole of Mg produces 1 mole of MgCl2.
So 0.412 moles of Mg produces 0.412 moles of MgCl2.
Now we transform 0.412 moles of MgCl2 into mass using the following formula: mass = moles x molar mass
Molar mass of MgCl2: 24.3 + (2*35.45) = 95.21 g/mol
Mass = 0.412 * 95.21
Mass = 39.2 g
Answer: The theoretical yield of MgCl2 is 39.2 g.
Which hydrogen below will have the greatest partial positive charge?Group of answer choicesHIHClHBrHFcannot determine
The hydrogen bonded to the most electronegative element will have the greatest partial positive charge. This is because electronegativity corresponds to the ability of the nucleus of an atom to attract the electrons involved in a chemical bond.
So the more electronegative, the more partial negative charge the atom will have.
Linus Pauling created a scale of the most electronegative elements, which can be of help in determining the intensity of polarization of different bonds:
F > O > N > C > Br > I > S > C > P > H
In this case, F is the most electronegative element.
So hydrogen will have the greatest partial positive charge bonded to F.
Answer: HF
Experiment 2: Copper(II) carbonate hydroxide produces one mole of water (=18.015 g/mol) for every two moles of solid product (=79.545 g/mol) produced. If 3.597 g of solid product were produced during the reaction, how many grams of water were realeased as water vapor?
How many moles of NaOH are present in 12.0mL of 0.110 M NaOH? Moles: _________
NaOH
M = molarity (mol/L)
[tex]M\text{ = }\frac{mass\text{ of solute}}{\text{molecular mass of solute x volume of solution (L)}}=\frac{moles\text{ of solute}}{\text{volume of solution(L)}}[/tex][tex]M=0.110\text{ }\frac{mol}{L}=\text{ }\frac{moles\text{ of NaOH}}{0.012L}[/tex]12.0 ml = 0.012 L
[tex]\text{moles of NaOH = 0.11 }\frac{mol}{L}x0.012L=1.32x10^{-3\text{ }}moles\text{ of NaOH}[/tex]Answer: moles of NaOH = 1.32x10^-3 moles
[tex]\text{moles NaOH = 1.32x10}^{-3}moles\text{ = 0.00132 moles NaOH}[/tex]Aluminum reacts with chlorine gas to form aluminum chloride. (a) If 35g of aluminum reacts with excess chlorine, how many grams of aluminum chloride will form. (b) How many grams of chlorine will react completely with 42.8 g of aluminum 2Al + 3Cl2 ==> 2AlCl3
Answer
(a) 172.848 grams
(b) 168.584 grams
Explanation
The balanced equation for the reaction of aluminum with chlorine gas is:
[tex]2Al+3Cl_2\rightarrow2AlCl_3[/tex](a) Mass of Al = 35 g
From the Periodic Table;
Molar mass of Al = 27 g/mol
Molar mass of AlCl₃ = 133.34 g/mol
From the balanced equation above; 2 moles Al produced 2 moles AlCl₃
So in grams, 2 mol x 27 g/mol = 54 g Al produced 2 mol x 133.34 g/mol = 266.68 g AlCl₃
Therefore, 35 g Al will form:
[tex]\frac{266.68\text{ g AlCl}_{3}\text{ }\times35\text{ g Al}}{54\text{ g Al}}=172.848\text{ g AlCl}_{3}[/tex]172.848 grams of aluminum chloride will be formed.
(b) Mass of Al = 42.8 g
Also from the Periodic Table; the molar mass of Cl₂ = 70.90 g/mol
From the equation above; 2 mol of Al requires 3 mol Cl₂.
In grams, 2 mol x 27 g/mol = 54 g Al requires 3 mol x 70.90 g/mol = 212.7 g Cl₂
Hence, 42.8 g Al will react with:
[tex]\frac{42.8\text{ g Al }\times212.7\text{ g Cl}_{2}}{54\text{ g Al}}=168.584\text{ g Cl}_{2}[/tex]168.584 grams of chlorine will react completely with 42.8 g of aluminum
A quantity of 3.30 × 102 mL of 0.500 M HNO3 is mixed with 3.30 × 102 mL of 0.250 M Ba(OH)2 in a constant-pressure calorimeter of negligible heat capacity. The initial temperature of both solutions is the same at 18.46°C. The heat of neutralization when 1.00 mol of HNO3 reacts with 0.500 mol Ba(OH)2 is −56.2 kJ/mol. Assume that the densities and specific heats of the solution are the same as for water (1.00 g/mL and 4.184 J/g · °C, respectively). What is the final temperature of the solution?
The final temperature of the solution is 20 °C.
Given that :
volume of HNO₃ = 0.33 L
molarity = 0.500 M
no. of moles HNO₃ = 0.33 × 0.500
= 0.165 mol
moles of Ba(OH)₂ = 0.33 × 0.250
= 0.082 mol
Q = ΔH × n
Q = - 52600 J/mol × 0.165 mol
Q = - 8679 J
total volume = 330 mL +330 mL = 660 mL
Density = mass / volume
mass = 1 g/mL × 660 mL
mass = 660 g/mL
now, the change in temperature can be calculated by following formula :
Q = mc ( ΔT )
Q = mc ( T2 - T1 )
- 8679 = 660× 4.184 ( T2 - 18.46 °C)
T2 = 20 °C
Thus, A quantity of 3.30 × 10² mL of 0.500 M HNO3 is mixed with 3.30 × 10² mL of 0.250 M Ba(OH)₂ in a constant-pressure calorimeter of negligible heat capacity. The initial temperature of both solutions is the same at 18.46°C. The heat of neutralization when 1.00 mol of HNO₃ reacts with 0.500 mol Ba(OH)₂ is −56.2 kJ/mol. Assume that the densities and specific heats of the solution are the same as for water (1.00 g/mL and 4.184 J/g · °C, respectively). the final temperature of the solution is 20 °C.
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Balance the chemical equation below using the smallest possible whole number stoichiometric coefficients.
Na(s) + O₂(g) → Na₂O₂ (s)
Answer: 2Na(s)+O₂(g) → Na₂O₂ (s)
Explanation: Since there is only one sodium on the left side of the equation and 2 on the right all you have to do is put a 2 in front of the sodium on the left
Select all possible problems associated with using nuclear fusion reactions as an energy source. Nuclear fusion occurs at temperatures of millions of degrees Celsius.Research reactors require more energy to maintain these temperatures than the energy the reaction produces.Nuclear fusion occurs at negative degree Celsius temperatures to create unstable reactions to use as an energy sourceIt is difficult to contain the fusion reaction under such extreme conditions.
Answer:
[tex]A,B\text{ and D}[/tex]Explanation:
Here, we want to select the possible problems with nuclear fusion
Nuclear fusion refers to a nuclear reaction wherein two or more daughter nuclei combines to give a larger nucleus
Let us look at the options one after the other to check which of them is correct
a) This is correct
The temperature accompanying nuclear reactions is millions of degrees celsius which are very high
b) This is Correct
This is the major reason why there are currently no nuclear reactors that use fusion to provide energy
c) This is wrong
They occur at very high temperatures. The nuclei need very high energy to send them into kinetic motion
d) This is correct
It is quite difficult to contain a fusion reaction due to the conditions surrounding it and that is one of the reasons why there are no commercial nuclear reactors that use fusion as an energy source
9. Which statement provides evidence that supports the Big Bang Theory?* 2 points
O the universe began as a very high density singularity
Small spiral galaxies become larger elliptical galaxies
Dark matter makes up the majority of matter in the galaxy.
The chemical makeup of the universe has changed dramatically
The statement the chemical makeup of the universe has changed dramatically provides evidence that supports the Big Bang Theory (Option D).
What is the Big Bang Theory?The Big Bang Theory is a widely accepted theory in physics that states all the universe began with a huge explosion and form then matters expanded in space at the same time that it is cooling.
Therefore, with this data, we can see that the Big Bang Theory states that the chemical composition of the universe associated with hydrogen and helium modified since this explosion.
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Answer:
d
Explanation:
9. Which of the following shows whose model?a. Bohrb. Daltonc. Rutherfordd. Thomson
Answer
d. Thomson
Explanation
The given model shown above is Thomson's model of an atom.
In 1898, J. J. Thomson proposed that an atom is shaped like a sphere with a radius of approximately 10⁻¹⁰m, where the positive charge is uniformly distributed as shown in the model given. The electrons are embedded in this sphere so as to give the most stable electrostatic arrangement.
Thus, Thomson's model of an atom is also referred to as the watermelon model, the plum pudding model or the raisin pudding model.
An important aspect of Thomson's model of an atom is that it assumes that the mass of the atom is uniformly distributed over the atom. The model was successful in explaining the overall neutrality of the atom.
How many moles of chromium metal, Cr, are in a 260 gram piece of chromium?
In order to answer this question we will use the molar mass of Chromium, which is 52 g/mol, that means that in every 1 mol of Cr, we will have 52 grams of it:
52 g = 1 mol
260 g = x moles
52x = 260
x = 5 moles of Chromium
Some hydrogen and iodine are mixed at 229 degrees Celsius in a 1.00L container. When equilibrium is established, the following concentrations are present: [HI] = 0.490 M, [H2] = 0.080 M, [I2] = 0.060 M. If an additional 0.300 mol of HI is then added, what concentration will be present when the new equilibrium is established?
The concertation of the HI that would be present in the new equilibrium position is 0.15 M.
What is the new equilibrium position?We have to first obtain the equilibrium constant that we have under the initial conditions and then we have; H2 + I2 ------> 2HI
K = [HI]^2/[H2] [I2]
K = (0.490)^2/(0.080) (0.060)
K = 0.2401/(0.080) (0.060)
K = 50
Again;
H2 + I2 ------> 2HI
Initial 0.080 0.060 0.060
concentration +x +x -2x
Equilibrium 0.080 + x 0.060 + x 0.490 - 2x
50 = (0.490 - 2x)^2/( 0.080 + x) (0.060 + x)
Working through the quadratic we have;
46x^2 + 10.2 x - 0.38 = 0
x = 0.32 M
In each case we now have;
H2 = 0.080 + 0.32 = 0.4 M
[I2] = 0.060 + 0.32 = 0.38 M
[HI] = 0.790 - 2( 0.32 ) = 0.15 M
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A testable question is, “How does the amount of exercise affect heart rate and breathing rate?” Which is a controlled variable?O Amount of exerciseO Heart rateO Breathing rateO Temperature in the room
Answer
Temperature of the room
Explanation
The room temperature can be controlled compared to all other options.
Calculate the number of photons having a wavelength of 16.0 um required to produce 2.3KJ of energy (Note => 16.0 um = 16.0 * 10^6 m & 2.3KJ = 2300 J)
The number of photons having a wavelength of 16.0 um required to produce 2.3KJ of energy is 1.85 x 10¹⁹
What are photons?Photons are defined as a basic particle that is both the force carrier for the electromagnetic force and a quantum of the electromagnetic field, which includes electromagnetic radiation like light and radio waves.
It can also be defined as a discrete bundle of electromagnetic energy is what is known as a light particle.
Energy = 2.3 KJ
Wavelength = 16.0 x 10⁶ m
Energy = hc / ∧
= 6.63 x 10²⁴ x 3 x 10³ / 16.0 x 10⁶
= 1.24 x 10¹⁹ J
Number of photons used = 2.3 KJ / 1.24 x10¹⁹
= 1.85 x 10¹⁹
Thus, the number of photons having a wavelength of 16.0 um required to produce 2.3KJ of energy is 1.85 x 10¹⁹
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What is the hydrogen ion and hydroxide ion concentration for a pH of 4.478? Is the solution acid or base?
Answer
The hydrogen ion concentration, [H⁺] is 3.327 x 10⁻⁵ M
The hydroxide ion concentration [OH⁻] is 3.01 x 10⁻¹⁰ M
The solution is acid.
Explanation
pH is a measure of how acidic or basic a solution is. The range goes from 0 - 14, with 7 being neutral. A pH of less than 7 indicates acidity, whereas a pH of greater than 7 indicates a base. pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the solution.
Since pH of the solution is 4.478, then it means the solution is acid.
The hydrogen ion concentration, [H⁺] of the solution can be calculated using the pH formula.
[tex]pH=-log[H^+][/tex]Substituting pH as 4.478 into the formula, we have
[tex]\begin{gathered} 4.478=-log[H^+] \\ \\ Multiply\text{ }through\text{ }by\text{ }minus\text{ }(-) \\ \\ log[H^+]=-4.478 \\ \\ .[H^+]=10^{-4.478} \\ \\ .[H^+]=3.327\times10^{-5}\text{ }M \end{gathered}[/tex]The hydrogen ion concentration, [H⁺] is 3.327 x 10⁻⁵ M
The relation between the hydrogen ion concentration, [H⁺] and hydroxide ion concentration [OH⁻] is
[tex].[H^+]\times[OH^-]=10^{-14}[/tex]So, substituting [H⁺] as 3.327 x 10⁻⁵ M, we have:
[tex]\begin{gathered} 3.327\times10^{-5}\times[OH^-]=10^{-14} \\ \\ Divide\text{ }both\text{ }sides\text{ }by\text{ }3.327\times10^{-5} \\ \\ \frac{3.327\times10^{-5}\times\times[OH^-]}{3.327\times10^{-5}}=\frac{10^{-14}}{3.327\times10^{-5}} \\ \\ .[OH^-]=3.01\times10^{-10}\text{ }M \end{gathered}[/tex]Hence, the hydroxide ion concentration [OH⁻] is 3.01 x 10⁻¹⁰ M
The wavelength of green light from a traffic signal is approximately 5.2 * 10^7 m. Calculate its frequency
If the wavelength of green light from a traffic signal is approximately 5.2 ×10⁷ m , then the frequency of the light would be 5.769 × 10¹⁶ Hz .
What is Wavelength?It can be understood in terms of the distance between any two similar successive points across any wave for example wavelength can be calculated by measuring the distance between any two successive crests.
C = λν
The frequency of the green light = 3 × 10⁸ / 5.2 ×10⁷
= 5.769 × 10¹⁶ Hz
Thus , If the wavelength of green light from a traffic signal is approximately 5.2 ×10⁷ m , then the frequency of the light would be 5.769 × 10¹⁶ Hz .
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4. Which atom (magnesium or chlorine) has a higher ionization energy?___________________________(you should also be prepared to answer the question if asked for lower ionization energy)4a. Explain why the atom has a higher ionization energy. Include the definition of ionization energy and the reason why the atom you chose would have a higher value.
Answer:
The Chlorine atom has higher ionization energy.
Explanation:
Ionization energy is the energy needed to separate an electron from an atom of an element in the gaseous state.
In the Periodic Table of Elements, Ionization energy increases from bottom to top (in a group), and increases from left to right (in a period).
In the folowing drawing we can see the variation of the Ionization energy and the location of the magnesium atom and chlorine atom:
Magnesium atom and Chlorine atom are located in the same period, but Mg is in group 2 (left side) and Cl in in group 17 (right side), so the Chlorine atom has higher ionization energy.
Use the concentrations given to determine whether each of the following is acidic, neutral, or basic.A. [H+] = 4.3 × 10-3 mol/LB. [H+] = 9.8 × 10-12 mol/LC. [OH-] = 4.8 × 10-2 mol/L
We have the concentration of H+ ions, from these concentrations we can find the pH values of the solutions with the following equation:
[tex]pH=-log\lbrack H^+\rbrack[/tex]Where [H+] is the concentration of H+ ions.
Now, the acidity or basicity of a solution depends on the pH value. A solution above 7 will be basic, below 7 will be acidic, and equal to 7 will be neutral.
Let's determine the pH value for each solution:
[tex]\begin{gathered} pH=-log\lbrack4.3\times10^{-3}mol/L\rbrack \\ pH=2.4 \end{gathered}[/tex][tex]\begin{gathered} pH=-log\lbrack9.8\times10^{-12}mol/L\rbrack \\ pH=11.0 \end{gathered}[/tex][tex]\begin{gathered} pH=-log\lbrack4.8\times10^{-2}mol/L\rbrack \\ pH=1.3 \end{gathered}[/tex]So, we have that:
A. [H+] = 4.3 × 10-3 mol/L. pH=2.4. Acidic
B. [H+] = 9.8 × 10-12 mol/L pH = 11.0 Basic
C. [OH-] = 4.8 × 10-2 mol/L pH=1.3 Acidic
Fe2O3 + 3H2 = 2Fe + 3H2OCalculate how many grams of iron can be made from 24.5 grams of iron (III) oxide.
Explanation:
Iron (III) oxide will react with hydrogen gas to produce iron and water. They will react according to the following equation.
Fe₂O₃ + 3 H₂ -----> 2 Fe + 3 H₂O
We have to find the grams of Fe that can be made from 24.5 g of Fe₂O₃. So, first we have to convert those grams into moles using the molar mass of iron (III) oxide.
molar mass of Fe₂O₃ = 159.69 g/mol
mass of Fe₂O₃ = 24.5 g
moles of Fe₂O₃ = 24.5 g * 1 mol/(159.69 g)
moles of Fe₂O₃ = 0.153 mol
Fe₂O₃ + 3 H₂ -----> 2 Fe + 3 H₂O
According to the coefficients of the equation, we know that 1 mol of Fe₂O₃ will react with 3 moles of H₂ to give 2 moles of Fe and 3 moles of H₂O. So the molar ratio between Fe₂O₃ and Fe is 1 to 2. We can use that relationship to find the number of moles of Fe that can be made from 0.153 moles of Fe₂O₃.
1 mol of Fe₂O₃ : 2 moles of Fe molar ratio
moles of Fe = 0.153 moles of Fe₂O₃ * 2 moles of Fe/(1 mol of Fe₂O₃)
moles of Fe = 0.306 moles
So we found that we can produce 0.306 moles of Fe from 0.153 moles of Fe₂O₃ or 24.5 g of it. Finally we can convert the 0.306 moles of Fe into grams using the molar mass of Fe.
molar mass of Fe = 55.85 g/mol
mass of Fe = 0.306 moles * 55.85 g/mol
mass of Fe = 17.1 g
Answer: 17.1 g of iron can be made from 24.5 g of iron (III) oxide.
A scientist uses a graduated cylinder to measure 100.0 mL of gasoline for an experiment. The density of gasoline is 0.774 g/mL. What is the mass of this gasoline sample?
Answer:
100ml x 0.774
divide by 4
x by 8
When dealing with diatomic elements like oxygen, the atoms are not separate; they always come in pairs. Therefore, one mole of oxygen molecules would weigh _______ grams and not 16 grams
32 grams
Explanations:What are diatomic elements?Diatomic elements are elements that contain two atoms chemically bonded together.
When looking for the molar mass of a diatomic element, the number of atoms in the element is multiplied by the molar mass of the element.
For instance, oxygen is a diatomic element with the chemical symbol of O₂. This shows that the molar mass of oxygen will be given as:
[tex]\begin{gathered} molar\text{ mass of O}_₂=2\times16g\text{/mol} \\ molar\text{ mass of }O_2=32g\text{/}mol \end{gathered}[/tex]This shows that one mole of oxygen molecules would weigh 32 grams and not 16 grams.
