Answer: 0.01 moles (I am guessing)
Explanation:
Firstly, cm3 and ml are equal to one another, therefore 250cm3 can also be written as 250 ml. I Googled and found that ideally, one mole of gas will occupy a volume of 22.4 L (22,400 ml) at s.t.p. 250 ml out of 22,400 ml is 0.01 rounded, therefore I assume that is the answer. About 0.01 mole occupies 250 cm3 at s.t.p.
Chromium is dissolved in sulfuric acid according to the following equation: Cr + H2SO4 ⇒ Cr2 (SO4) 3 + H2
a) How many grams of Cr2 (SO4) 3 can be obtained by reacting 165 g of 85.67% H2SO4 of purity?
b) If 485.9 g of Cr2 (SO4) 3 are obtained, what is the yield of the reaction?
Answer:
[tex]\large \boxed{\text{a)188.4 g; b) 98.67 $\, \%$}}[/tex]
Explanation:
We will need a balanced chemical equation with masses and molar masses, so, let's gather all the information in one place.
Mᵣ: 98.08 392.18
2Cr + 3H₂SO₄ ⟶ Cr₂(SO₄)₃ + 3H₂
To solve the stoichiometry problem, you must
Use the molar mass of H₂SO₄ to convert the mass of H₂SO₄ to moles of H₂SO₄ Use the molar ratio to convert moles of H₂SO₄ to moles of Cr₂(SO₄)₃ Use the molar mass of Cr₂(SO₄)₃ to convert moles of Cr₂(SO₄)₃ to mass of Cr₂(SO₄)₃
a) Mass of Cr₂(SO₄)₃
(i) Mass of pure H₂SO₄
[tex]\text{Mass of pure} = \text{165 g impure} \times \dfrac{\text{85.67 g pure} }{\text{100 g impure}} = \text{141.36 g pure}[/tex]
(ii) Moles of H₂SO₄
[tex]\text{Moles of H$_{2}$SO}_{4} = \text{141.36 g H$_{2}$SO}_{4} \times \dfrac{\text{1 mol H$_{2}$SO}_{4}}{\text{98.08 g H$_{2}$SO}_{4}} = \text{1.441 mol H$_{2}$SO}_{4}[/tex]
(iii) Moles of Cr₂(SO₄)₃
The molar ratio is 1 mol Cr₂(SO₄)₃:3 mol H₂SO₄ [tex]\text{Moles of Cr$_{2}$(SO$_{4}$)}_{3} = \text{1.441 mol H$_{2}$SO}_{4} \times \dfrac{\text{1 mol Cr$_{2}$(SO$_{4}$)}_{3}}{\text{3 mol H$_{2}$SO}_{4}} = \text{0.4804 mol Cr$_{2}$(SO$_{4}$)}_{3}[/tex]
(iv) Mass of Cr₂(SO₄)₃ [tex]\text{Mass of Cr$_{2}$(SO$_{4}$)}_{3} = \text{0.4804 mol Cr$_{2}$(SO$_{4}$)}_{3} \times \dfrac{\text{392.18 g Cr$_{2}$(SO$_{4}$)}_{3}}{\text{1 mol Cr$_{2}$(SO$_{4}$)}_{3}} = \textbf{188.4 g Cr$_{2}$(SO$_{4}$)}_{3}\\\text{The mass of Cr$_{2}$(SO$_{4}$)$_{3}$ formed is $\large \boxed{\textbf{188.4 g}}$}[/tex]
b) Percentage yield
It is impossible to get a yield of 485.9 g. I will assume you meant 185.9 g.
[tex]\text{Percentage yield} = \dfrac{\text{Actual yield}}{\text{Theoretical yield}} \times 100 \, \% = \dfrac{\text{185.9 g}}{\text{188.4 g}} \times 100 \, \% = \mathbf{98.67 \, \%}\\\\\text{The percentage yield is $\large \boxed{\mathbf{98.67 \, \%}}$}[/tex]
how many moles of copper are equivalent to 3.44x10^23 atoms of copper?
Answer:
0.571moles
Explanation:
The Avogrado's number or constant denoted by NA will be used for this question.
The Avogrado's number = 6.022 × 10^23 particles, is contained in 1 mole of a substance.
To get the number of atom/particles in a substance, the formula: N= n × NA is used.
Where; N= Number of atoms in
substance
n= number of moles
NA= Avogadro's constant
Hence, to find the number of moles of copper equivalent to 3.44 × 10^23, we say: n= N / NA
That is, n = 3.44 × 10^23 / 6.022 × 10^23
= 0.5712
Therefore, 0.571 moles of Copper (Cu) is equivalent to 3.44 × 10^23 atoms of Copper.
Which of the following statements is true? A. Isotopes of the same element have the same number of protons and neutrons. B. Isotopes have the same physical properties as the normal atom but different chemical properties. C. Isotopes have the same chemical properties as the normal atom but different physical properties. D. If an isotope of one element has the same atomic mass as another element, they will have the same properties.
Answer:
B
Explanation:
Isotopes have the same number of protons but different number of neutrons.
The true statement is,
Isotopes have the same chemical properties as the normal atom but different physical properties.So, option C is correct one.
What is isotopes?The elements have same number of proton but different number of neutrons.Example: hydrogen, deuterium, tritiumWhy isotopes of same elements have different physical properties?The isotopes have different physical properties like freezing point , mass, melting or boiling point etc because they have different mass number .
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name Two soft metals which can be cut with a knife.
Answer:
lithium, and sodium can be cut with a knife
An atom X has a proton number of 19 and relative atomic mass of 39.
(i) How many electrons, protons and neutrons are there in an atom of X?
(ii) How many electrons will there be in the outer energy level (shell) of an atom of X?
(iii) What is the electronic configuration of X?
Answer:
1) electron=19 Proton=19 Neutron=39-19=20
2) 1
3) in pic
Answer:
(i)electrons = 19; Protons = 19 Neutrons =39-19=20
(ii) 1
(iii) 2,8,8,1
Hope this helps.
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If an object's mass is 70 g, and its volume is 10cm cubed, what is its density?
If an object's mass is 70 g, and its volume is 10cm cubed, its density is 7 centimeter cube.
What is density?The density of any solid substance is the unit of the area occupied by it in per centimeter of the cube of the volume in the given sample and calculated by dividing the mass and the volume of the compound unit will be centimeter cube.
The mass of the given object is 70 gram and the volume is given is 10 cm to find the density,
Density = mass of object / volume of object
substituting the value in the formula,
Density = 70 / 10
Density = 7 centimeter cube.
Therefore, the density of the given object will be 7 centimeter cube if an object's mass is 70 g, and its volume is 10cm cubed.
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how much energy has your body used, in joules, if your health device indicates that 450 calories were burned during your workout
Answer:
Total energy consumed = 1,882.8 joules
Explanation:
Given:
Calories burned = 450 calories
Find:
Total energy consumed
Computation:
1 calorie = 4.184 joules
So,
450 calories = 4.184 × 450
450 calories = 1,882.8 joules
Total energy consumed = 1,882.8 joules
What happens when a chlorine atom gains an electron in its outer energy shell? A. It has an increase in the number of protons B. It becomes a negative ion C. It becomes a positive ion D. It has a decrease in the number of neutrons
Answer:
When a chlorine atom gains an electron, its outermost principal energy level achieves an octet. In this case, the ion has the same outermost shell as the original atom, but now that shell has eight electrons in it. Once again, the octet rule has been satisfied.
Explanation:
What would be the pH of an HNO3 solution if the [H+] = 3.26 x 10-6 moles/liter? 5.49 4.67 6.32
Answer:
5.49
Explanation:
pH = - log[3.26 x 10-6] =5.49
which of the following molecules would you expect to be optically active
1. CCl2F2
2. 2-methyl butane
3. butan-2-ol
Answer:
waaaaaaaaaaqwwwwwwwwwwww
Which term is defined as “anything that has mass and occupies space”? a -compound b - element c - substance d - matter
Answer:
D) Matter
Explanation:
How do weathering and deposition differ? Weathering breaks down rocks; deposition leaves them in new places. Weathering has to do with air; deposition has to do with plants. Weathering occurs only in summer; deposition occurs year-round. Weathering can be chemical or physical; deposition is only chemical
Answer:
A. Weathering breaks down rocks; Deposition leaves them in new places.
Explanation:
Weathering is basically the complete process of rocks breaking apart. In contrast, deposition is when the rocks are moved and carried away from their original place and put in new locations.
Answer:
a
Explanation:
The melting points of ionic compounds _____
Explanation:
ionic compounds have high melting points
What is the independent variable of Smithers experience?
Please help controls and variables simpson? Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special...
Answer:
Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're ... Group A is given the special juice to drink while they work. Group ... 1. Control Group. Group B. 2. Independent Variable. volume of special juice.
Explanation:
Answer:
1. Group B
2. The juice
3. The number of stacks of paper
4. the juice did not help improve a quicker process
5. Group A can be given the juice, Group B can be given the juice without the special ingredient
USE QUIZLET FLASH CARDS IT CAN HELP YOU WITH A LOT OF QUESTION
Define freezing....... Correct and detailed answers will be marked as Brainliest.
The transformation of liquid into solid when it reaches when it's temperature is below freezing point.
Answer:
Freezing:
When liquid is converted to solid, the process is called freezing.
Conditions for freezing:
1) Temperature must be lowered.
2) The temperature should be below 0 degree centigrade.
Example:
The conversion of "liquid water" into "ice".
=> We can use a "freezer" to freeze things.
convert 0.5 seconds to milliseconds and .02 km to meters
Answer:
0,5 seconds = 500 millisecondes
2 km = 200 meters
Explanation:
how many carbon atoms are in .650 gram tablet of aspirin (C9H8O4)?
Answer:
For example, in a molecule of aspirin, C9H8O4, there are 9 carbon atoms, 8 hydrogen atoms and 4 oxygen atoms. compound.
Explanation:
The carbon atoms are in 0.650 gram tablet of aspirin (C9H8O4) is 3.24 x 10² atoms.
What are atoms?Atoms are defined as the smallest unit of matter that can be divided without releasing electrically charged particles.
After the Big Bang, the building blocks of matter were generated is known as atoms.
Molar mass of aspirin = 180.2 g
Number of carbon atoms
= 0.650 g x 1 mole aspirin / 180.2 g x 9 / 1 mole aspirin
= 3.24 x 10² atoms
Thus, the carbon atoms are in 0.650 gram tablet of aspirin (C9H8O4) is 3.24 x 10² atoms.
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Use the periodic table to determine which element the following spin diagram
represents:
(Using the image)
A. nitrogen
B. Oxygen
C. None of these
D. Boron
Answer:
B. Oxygen
Explanation:
Basically count each arrow since each arrow represents an electron. Then use the periodic table to find the element with 8 electrons, which is oxygen. Also, if you know the orbital patterns, you can identify that the 2p orbital represents an element in Group 16.
How is the Law of Conservation of Mass being followed in a voltaic cell with a zinc anode and a copper cathode? A. No mass is lost because electrons are flowing, not atoms. B. The mass lost by the copper electrode is gained by the zinc cathode. C. The Law of Conservation of Mass is not followed when electricity is generated. D. The mass lost by the zinc electrode is gained by the copper cathode.
Answer:
b
Explanation:
In the given scenario, the mass lost by the copper electrode is gained by the zinc cathode. The correct option is B.
What is Law of Conservation of Mass?The law of conservation of mass asserts that mass is neither created nor destroyed in a chemical reaction.
As electrons are lost at the anode, metal cations construct and dissipate into the solution, reducing the anode's mass through corrosion. The anode's lost electrons attract to the positively charged cathode and flow through the wire.
Thus, the correct option is B.
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how to unscramble dtneinreigs
Answer:
Ingredients OR tenderising
Explanation:
How many significant figures
are in this number?
107.051
Answer:
there are 6 significant figures in 107.051
Answer:
There Are 6 Significant Numbers
Explanation: But some problems stop at the . so it could 3 if im right but go with 6!
what is the scientific term for salt
Answer:
The scientific term for table salt is Sodium chloride.
Explanation:
The answer is sodium chloride.
It is composed of sodium and chloride. Like,
[tex] {na}^{ + } + {cl}^{ + } = nacl[/tex]
so, it's name is sodium chloride.
Three determinations were made of the following percentage of oxygen in mercuric oxide. The results were 7.40%, 7.43%, and 7.35%. What was the average percentage?
If the red car travels from 50 m to -25 m in 5 seconds, what is its velocity?
Answer:
V = 14m/s
Explanation:
velocity is the rate of change in displacement
V = (change in displacement)/time
V = (50 - (-20) )/5
V = (70)/5
V = 14m/s
Question number 4..
Answer:
I think it's 7089 because that's my answer to your questions
What are half reaction
Answer:
When you don't have a complete reaction.
Explanation:
Happens a lot between a solvent and a solute. The solute may not bind well with the solvent I.e. water.
What group is calcium and sodium in?
Answer:
Calcium: Alkaline Earth
Sodium: Alkali Metal
Hope it helps!
Answer:
Calcium is in Alkaline Earth
Sodium is in Alkali Metal
What is the name of this compound? H single bonded to N with a pair of electron dots above and a single bond to H below, single bonded to the right to C with H above and below, and another C with H above, below, and right.
Answer:
Ethanamine (also known as ethylamine)
Explanation:
The compound that is requested by the question is ethanamine. Its trivial name is ethylamine.
It is a compound that contained the ethyl moiety (CH3CH2-) as well as the amine moiety (-NH2).
Ethanamine has a structure that can easily be determined by the statements in the question.
The structure of ethanamine is shown in the image attached.
Answer:
What is the name of this compound?
H H
│ │
H ── N ── C ── C ── H
│ │ │
H H H
❌ A) ethanal
✔️B) ethylamine❌ C) ethanoic acid
❌ D) methyl ethanoate
I Took Question Test And Have Day.
What u learned about the states of matter?
Answer:t
Explanation:
In everyday life, four states of matter are visible: solid, liquid, gas, and plasma.
Of course, matter also has other states, such as Bose-Einstein density and Fermion density, but these states are only observed under certain conditions.
What is the atomic number of copper
Answer:
29
Explanation:
Copper is a chemical element with the symbol Cu and atomic number is 29
Explanation: