0.042 moles of Hydrogen evolved
Further explanationGiven
I = 1.5 A
t = 1.5 hr = 5400 s
Required
Number of Hydrogen evolved
Solution
Electrolysis of water ⇒ decomposition reaction of water into Oxygen and Hydrogen gas.
Cathode(reduction-negative pole) : 2H₂O(l)+2e⁻ ⇒ H₂(g)+2OH⁻(aq)
Anode(oxidation-positive pole) : 2H₂O(l)⇒O₂(g)+4H⁻(aq)+4e⁻
Total reaction : 2H₂O(l)⇒2H₂(g)+O₂(g)
So at the cathode H₂ gas is produced
Faraday : 1 mole of electrons (e⁻) contains a charge of 96,500 C
[tex]\tt mol~e^-=\dfrac{Q}{96500}[/tex]
Q = i.t
Q = 1.5 x 5400
Q = 8100 C
mol e⁻ = 8100 : 96500 = 0.084
From equation at cathode , mol ratio e⁻ : H₂ = 2 : 1, so mol H₂ = 0.042
please help..............
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How are food webs and food chains related? HELP IF YOU WANT BRAINLEIST!!
Food webs only contain consumers.
Food webs consist of only one food chain.
Food webs are made of many food chains.
Food webs only contain producers.
Answer: Food webs are made of many food chains is the answer.
Explanation:
Food web consists many food chains.
PlEasE help ASAP
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Answer:
message me on messenger johnpatrick so I can help you
(1) Phosphorus silicon is a semi-conductor
When Silicone is altered with Phosphorus, 4 of its electrons form covalent bonding and the 5th electron becomes delocalized and thus it increases electrical conduction
Answer:
blue blah blue blah
Explanation:
A solution is made by mixing 49.g of chloroform CHCl3 and 73.g of acetyl bromide CH3COBr. Calculate the mole fraction of chloroform in this solution. Round your answer to 2 significant digits.
Answer: The mole fraction of chloroform in this solution is 0.41
Explanation:
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]
a) moles of [tex]CHCl_3[/tex]
[tex]\text{Number of moles}=\frac{49g}{119g/mol}=0.41moles[/tex]
b) moles of [tex]CH_3COBr[/tex]
[tex]\text{Number of moles}=\frac{73g}{123g/mol}=0.59moles[/tex]
To calculate the mole fraction, we use the formula:
[tex]\text{Mole fraction of a component}=\frac{\text{Moles of the component}}{\text{total moles}}[/tex]
[tex]\text{Mole fraction of chloroform}=\frac{\text{Moles of chloroform}}{\text{total moles}}=\frac{0.41}{0.41+0.59}=0.41[/tex]
The mole fraction of chloroform in this solution is 0.41
Consider the reaction of solid aluminum iodide and potassium metal to form solid potassium iodide and aluminum metal.The balanced chemical equation is AlI₃(s) + 3 K(s) → 3 KI(s) + Al(s).Given the reaction has a percent yield of 67.8%, what is the mass in grams of aluminum iodide that would be required to yield an actual amount of 30.25 grams of aluminum?
Answer:
674.26 g of AlI₃
Explanation:
We'll begin by calculating the theoretical yield of aluminum (Al). This can be obtained as follow:
Percentage yield of Al = 67.8%
Actual yield of Al = 30.25 g
Theoretical yield of Al =?
Percentage yield = Actual yield /Theoretical yield × 100/
67.8% = 30.25 / Theoretical yield
67.8 / 100 = 30.25 / Theoretical yield
0.678 = 30.25 / Theoretical yield
Cross multiply
0.678 × Theoretical yield = 30.25
Divide both side by 0.678
Theoretical yield = 30.25 / 0.678
Theoretical yield of Al = 44.62 g
Next, we shall determine the mass of AlI₃ that reacted and the mass of Al produced from the balanced equation. This can be obtained as follow:
AlI₃(s) + 3K(s) → 3KI(s) + Al(s)
Molar mass of AlI₃ = 27 + (3×127)
= 27 + 381 = 408 g/mol
Mass of AlI₃ from the balanced equation = 1 × 408 = 408 g
Molar mass of Al = 27 g/mol
Mass of Al from the balanced equation = 1 × 27 = 27 g
Summary:
From the balanced equation above,
408 g of AlI₃ reacted to produce 27 g of Al.
Finally, we shall determine the mass of
AlI₃ required to produce 44.62 g of Al. This can be obtained as follow:
From the balanced equation above,
408 g of AlI₃ reacted to produce 27 g of Al.
Therefore, Xg of AlI₃ will react to produce 44.62 g of Al i.e
Xg of AlI₃ = (408 × 44.62)/27
Xg of AlI₃ = 674.26 g
Thus, 674.26 g of AlI₃ is needed for the reaction.
Balance the chemical equation below using the smallest possible whole number stoichiometric coefficients. FE2O3(s) Fe(s) O2(g)
Answer:
2Fe₂O₃(s) → 4Fe(s) + 3O₂(g)
Explanation:
The unbalanced reaction is:
Fe₂O₃(s) → Fe(s) + O₂(g)To balance the oxygen atoms, we put a 2 before Fe₂O₃ and a 3 before O₂(g) - so as to make the total of O atoms in both sides 6 -:
2Fe₂O₃(s) → Fe(s) + 3O₂(g)There are four Fe atoms on the left side and only one on the right side, so we put a 4 before Fe(s):
2Fe₂O₃(s) → 4Fe(s) + 3O₂(g)Now the equation is balanced: there is an equal number of both Fe and O atoms in both sides of the equation.
List all possible oxidation numbers for the elements. 21. Al
22. Bi
23. Ni
24. Xe
25. Pb
Answer:
21. Al (Aluminium)
+3 (most common), -1, -2, +1, +2
22. Bi (Bismuth)
+3 (most common), -3, -2, -1, +1, +2, +4, +5
23. Ni (Nickel)
+2 (most common), -2, -1, 0,+1, +3, +4
24. Xe (Xenon)
0 (most common), +1, +2, +4, +6, +8
25. Pb (Lead)
+2 (most common), +4 (most common), -4, -2, -1, +1, +3
Explanation:
Now we proceed to present the answers for each element:
21. Al (Aluminium)
+3 (most common), -1, -2, +1, +2
22. Bi (Bismuth)
+3 (most common), -3, -2, -1, +1, +2, +4, +5
23. Ni (Nickel)
+2 (most common), -2, -1, 0,+1, +3, +4
24. Xe (Xenon)
0 (most common), +1, +2, +4, +6, +8
25. Pb (Lead)
+2 (most common), +4 (most common), -4, -2, -1, +1, +3
What is the molecular formula for a compound with a molar mass of 42.08g/mol and an empirical formula of ch2
Answer:
[tex]C_3H_6[/tex]
Explanation:
Hello!
In this case, since the empirical formula is the smallest representation of the molecular formula, it is known that the times in which the empirical formula is into the molecular formula is a whole number and is computed by dividing the molar mass of the molecular formula by that of the empirical formula as shown below:
[tex]\frac{42.08g/mol}{12.01+1.01x2}= \frac{42.08g/mol}{14.03g/mol}=3[/tex]
Thus, the molecular formula times the empirical formula by 3 to obtain:
[tex]C_3H_6[/tex]
Regards!
What makes this inauguration different from the past?
Answer:
there's just a lot of drama around grumpy trumpy's StOlEN eLecTiOn which are all just fake claims. all his hardcore followers are brainwashed into believing anything he says, so people (especially people who are inside the capitol) fear that trump's followers might incite violence AGAIN even after they broke into the Capitol on the 6th.
That's why they have the National Guard and thousands of people to keep the building secure during Biden's Inauguration.
hope this helps!
g What amounts of 45% pure silver and 50% pure silver should be mixed to obtain 14 grams of 46% pure silver
Answer:
11.2g of the 45% pure silver and 2.8g of the 50% pure silver.
Explanation:
14g of 46% pure silver contains:
14g*46% = 6.44g of silver are required. Thus, we can write:
6.44 = X*50% + Y*45% (1)
Where X is the mass of 50% pure silver and Y the mass of 45% pure silver.
As the mass of the sample must be 14g:
14g = X + Y (2)
Replacing (2) in (1):
6.44 = (14-Y)*50% + Y*45%
6.44 = 7 - 0.5Y + 0.45Y
-0.56 = -0.05Y
Y = 11.2g of the 45% pure silver
And:
14g-11.2g = X
X =
2.8g of the 50% pure silver
The required amount to obtain 14g of 46% pure silver is 2.8g of 50% silver and 11.2g of 45% silver.
To solve this question, we can assume it's a mathematical problem more than a chemistry problem.
let x represent the amount of 45% of pure Ag
let y represent the amount of 50% of pure Ag
But from the question, we only need 14g from both x and y
We can write an equation to represent this
[tex]x+y=14...equation(i)[/tex]
likewise, we can say that
[tex]0.45x+0.50y=14*0.46\\0.45x+0.50y=6.44...equation(ii)[/tex]
Solving both equations simultaneously,
[tex]x+y=14...equation(i)\\0.45x+0.5y=6.44...equation(ii)[/tex]
from equation (i)
[tex]x+y=14\\x=14-y...equation(iii)[/tex]
substitute equation (iii) into equation (ii)
[tex]0.45x+0.5y=6.44\\x=14-y\\0.45(14-y)+0.5y=6.44\\6.3-0.45y+0.5y=6.44\\[/tex]
collect like terms
[tex]-0.45y+0.50y=6.44-6.3\\0.05y=0.14\\y=\frac{0.14}{0.05}\\y=2.8[/tex]
Now we know the value of the 50% Ag which is 2.8g. Let's substitute it's value into equation (i) and solve for x
[tex]x+y=14\\x+2.8=14\\x=14-2.8\\x=11.2g[/tex]
Learn more about definite proportions here
https://brainly.com/question/1496091
which of the following statements are part of the kinetic molecular theory ?
Answer: The average kinetic energy is proportional to the absolute temperature of the gas. Gas particles are in random motion. Gas particles have no volume. And the collisions between gas particles are elastic.
Explanation: I heard this question before, I think. Hope this helps!
Which of the following conditions does not affect equilibrium?
A. Particle Size
B. None of these
C. Concentration
D. Pressure
Answer:
B. None of these
Explanation:
The subatomic particle that is different in isotopes
Answer:
Neutrons
Explanation:
Subatomic particles are components atoms, and they include protons, electrons and neutrons. In different isotopes of an atom, the number of neutrons that the atom contains is what changes.
I hope this helps!
which element can form an oxide with the general formula m2o or mo where m is a metal
Answer:
Because the compound has a formula of M2O, the number of valence electrons of M should be 1. Therefore, (1) Group 1 is the correct answer because elements in group 1 have 1 valence electron.
Explanation:
What are the outcomes of the ice cap melting? Choose all that apply.
1. Light cannot be reflected back to the atmosphere
2. Sea level rises
3. Absorption of solar radiation leads to increase in ocean temperature
4. Ocean remains unaffected
Answer:
2. sea level rises sorry if it's wrong
Weather, erosion and deposition will change the environment over time. When water runs over rocks it can smooth out jagged edges and even leave streak on the surface of the rock. This is an example of _____________.
Answer:
erosion.
Explanation:
A 14.0 tank contains 250 g of methane (CH4) gas at 27 atm at 298 K. Accidentally, 190 g of CO2 was added to the tank. What will be the resulting pressure of the mixture in the tank? Assume that no CH4 leaked out as the CO2 gas waa being added.
Answer:
[tex]P=34.8atm[/tex]
Explanation:
Hello!
In this case, since the tank has a constant volume as well as temperature, we would be able to compute the resulting pressure via:
[tex]P=\frac{n_TRT}{V}[/tex]
Whereas the total moles are computed by adding the moles of each gas as shown below:
[tex]n_{CH_4}=250gCH_4*\frac{1molCH_4}{16.05gCH_4}=15.6molCH_4\\\\n_{CO_2}=190g CO_2*\frac{1molCO_2}{44.01gCO_2}=4.32molCO_2\\\\n_T= 15.6molCH_4+4.32molCO_2\\\\n_T=19.9mol[/tex]
Thus, we plug in the total pressure, temperature and volume to get the resulting pressure:
[tex]P=\frac{19.9mol*0.08206\frac{atm*L}{mol*K}*298K}{14.0L}\\\\P=34.8atm[/tex]
Best regards!
Why can you see solids and liquids, but not most gases?
Why can gases and liquids be paired but not solids?
The atoms and molecules in gases are much more spread out than in solids or liquids. They vibrate and move freely at high speeds. A gas will fill any container, but if the container is not sealed, the gas will escape. Gas can be compressed much more easily than a liquid or solid.
Balance the following chemical equation: N2H4+O2→ NO2+H2O
Answer:
N2H4 + 3O2 → 2NO2 + 2H2O
Explanation:
As ice cream freezes do the chemical properties of the substance change? Explain why or why not?
How many bonding and non-bonding electron pairs are found in the BF3 molecule?
Answer:
MARK AS BRAINLIEST
Explanation:
Boron trifluoride only has six valence electrons and is one of the relatively rare second period covalent molecules that disobeys the octet rule. There are three bonded groups and so no lone pairs. Six electrons implies three electron pairs and therefore a trigonal geometry.
3 bonding and 0 non-bonding electron pairs are found in the BF3 molecule.
What is bonding?Chemical Bonding refers to the formation of a chemical bond between two or more atoms, molecules, or ions to give rise to a chemical compound.
Boron trifluoride only has six valence electrons and is one of the relatively rare second-period covalent molecules that disobeys the octet rule.
There are three bonded groups and so no lone pairs. Six electrons imply three electron pairs and therefore a trigonal geometry.
Learn more about the bonding here:
https://brainly.com/question/10777799
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Two inductors are connected in series to a 120 volt, 60 Hz line. The values are .75 H and 1.47 H. The total inductive reactance is
Answer:
837.02 ohms
Explanation:
Step one:
Given data
Frequency= 60Hz
L1= 0.75H
L2= 1.47H
When inductors are connected in series, the total inductance is the sum of the individual inductance
Step two:
Inductor 1
[tex]Xl1= 2\pi fL\\\\Xl1= 2*3.142*60*0.75\\\\Xl1= 282.78 ohms[/tex]
Inductor 2
[tex]Xl2= 2\pi fL\\\\Xl2= 2*3.142*60*1.47\\\\Xl2= 554.24 ohms[/tex]
The total inductance is
=282.78+554.24
=837.02 ohms
The compound cobalt(II) bromide is a strong electrolyte. Write the transformation that occurs when solid cobalt(II) bromide dissolved in water. Be sure to specify states such as (aq) or (s).
Answer and Explanation:
The chemical formula for cobalt(II) bromide is CoBr₂. As it is a strong electrolyte, it dissociates into ions when dissolved in water, according to the following chemical equation:
CoBr₂(s) → Co²⁺(aq) + 2 Br⁻(aq)
Thus, the compound CoBr₂ dissociates in water producing 1 mole of cobalt(II) ions (Co²⁺) and 2 moles of bromide ions (Br⁻) per mole of CoBr₂. The ions are dissolved in water, so they are in the aqueous state (aq).
How many valence electrons these elements have
Answer:
Any element in group 1 has just one valence electron. Examples include hydrogen (H), lithium (Li), and sodium (Na). Any element in group 18 has eight valence electrons (except for helium, which has a total of just two electrons).
Explanation:
How many valence electrons does each element have?
The Group 1 atoms have 1 valence electron. The Group 2 atoms have 2 valence electrons. The Group 3 atoms have 3 valence electrons. The Group 4 atoms have 4 valence electrons.
I hope it's helpful
What mass of hydrogen is required to react with 24.7 g of nitrogen?
Answer:
10.80 g of H2
Explanation:
As per the equation, let us calculate the mole ratio. N2+3H2→2NH3. As per the equation one mole of nitrogen
How many electrons will the lithium atom give up to become stable?
a. 1
b. 2
c. 3
d. 4
Answer: 2
Explanation: that’s the answer for the quiz
Identify the products in the following chemical reaction: Multiply chose
2NaHCO3 + CaCl2 → CaCO3 + CO2 + 2NaCl + H2O
A. NaHCO3
B. CaCl2
C. CaCO3
D. CO2
E. NaCl
H2O
Answer:
C. CaCO3
D. CO2
E. NaCl
. H2O
A mixture of ethyne gas (C2H2) and methane gas (CH4) occupied a certain volume at a total pressure of 16.8 kPa. When the sample burned, the products were CO2 gas and H2O vapor. The CO2 was collected and its pressure found to be 25.2 kPa in the same volume and at the same temperature as the original mixture. What percentage of the original mixture was methane
Answer:
50%
Explanation:
Let assume that there are:
"a" moles of CH4 & "b" moles of C2H2
Then by applying the ideal gas equation:
PV = nRT
[tex]16.8 \times 10^3 \times V = (a+b)RT[/tex]
Make (a+b) the subject of the formula:
[tex](a+b) = \dfrac{16800 \ V }{RT} mol[/tex] --- (1)
Since 1 mole of CH₄ yields 1 mol of CO₂ & 1 mol of C₂H₂ yields 2 moles of CO₂
Then;
the total moles of CO₂ = (a +2b)
Now:
[tex]25.3 \times 10^3 \times V = (a+ 2b)RT[/tex]
[tex](a + 2b) = \dfrac{25200 \ V}{RT \ mol}[/tex] ---- (2)
∴
By solving the above equations
[tex]a = \dfrac{8400 \ V}{RT} \\ \\ b = \dfrac{8400 \ V}{RT}[/tex]
Hence, the estimate of the percentage of methane in the original mixture is:
[tex]= 100 \times \dfrac{a}{(a+b)}[/tex]
[tex]= 100 \times \dfrac{8400\dfrac{ \ V}{RT} }{8400\dfrac{ \ V}{RT} + 8400\dfrac{ \ V}{RT}}[/tex]
= 50%
QUESTION 4
How many significant figures are in the number 0.000020?
O A. 1
OB.2
O C.3
OD.4
Answer:
B) 2
Explanation:
There are two significant figures in given measurement,
2, 0
Significant figures:
1= The given measurement have four significant figures 1534.
2= All non-zero digits are consider significant figures like 1, 2, 3, 4, 5, 6, 7, 8, 9.
3= Leading zeros are not consider as a significant figures. e.g. 0.03 in this number only one significant figure present which is 3.
4= Zero between the non zero digits are consider significant like 107 consist of three significant figures.
5= The zeros at the right side e.g 2400 are also significant. There are four significant figures are present.
