Answer:
Rubbing your hands together converts mechanical energy to thermal energy. Turning on a light switch converts mechanical energy to electrical and radiant energy.
The melting points of ionic compounds _____
Explanation:
ionic compounds have high melting points
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]
In the image above the ruler is measuring in centimeters. The blue cylinder falls somewhere between 2.7cm and 2.8cm according to the ruler. Since we can estimate the last digit I would say that the length of the cylinder is 2.76cm. Since I am estimating any number 2.72cm or 2.78cm could also be correct.
Why would 2.755 not be a correct measurement according to estimating the last digit?
Answer:
The answer is below
Explanation:
Resolution is the smallest unit of measurement that can be measured by a measuring instrument. Each point on the ruler is 0.1 cm and the difference between any two points, about 0.01 cm cam be measured. The minimum measurement (resolution) that can be measured by the ruler is 0.01 cm (two decimals), therefore it cannot measure up to three decimal places such as numbers like 2.755.
what is the molarity of a 50.0 ml aqueous solution containing 10.0 grams of acetic acid, ch3cooh?
Answer:
3.34 M or 3.34 mol/L
Explanation:
The formula for molarity is moles of solution ÷ liters of solution. So, we have to convert grams into moles and mL to L.
To convert grams to moles, first find the molar mass of CH₃COOH by looking at the atomic mass of each individual element.
C - 2(12.01) = 24.02
H - 4(1.01) = 4.04
O - 2(16.00) = 32.00
= 60.06
Now divide the number of grams by the molar mass.
10.0 g CH₃COOH ÷ 60.06 g = 0.167 mol CH₃COOH
To convert milliliters to liters, divide by 1000.
50.0 mL ÷ 1000 = 0.05 L
Now we can calculate the molarity.
M = moles of solution ÷ liters of solution
= 0.167 mol ÷ 0.05 L
= 3.34 M or 3.34 mol/L
The molarity is 3.34 M.
Hope that helps.
It requires work to _____. A. stretch a spring only B. compress a spring only C. stretch or compress a spring
Answer:
C.
Explanation:
It requires work to stretch or compress a spring.
Answer:the answer is c
Explanation: i say that because with work you can do both of those things
You work in the special effects department of a movie studio. You are currently working on a superhero movie where the hero is very strong and
can punch through metal. For the next scene you need to replace a 6 inch by 6 inch square of a metal wall with a different material that will
crumble when the actor hits it. What could you use?
Answer:
either potassium or carbon, most likely carbon
Explanation:
the other two options are denser and more durable, making it harder for the actor to punch through
Polyurethane material is dense and durable, making it difficult for actors to claim themselves.
Why are props used in movies?Props are very important in storytelling. They complement and motivate the character, help the actor feel better than the "role", set the scene, set a specific time, place, and cultural setting, and sometimes the main part of the movie. It can even be the focus.
What material is used as a prop?Polyurethane Plastic: Rigid and Semi-Rigid. Create rigid and semi-rigid props using Polytek® polyurethane casting resin.Polyurethane foam. Polyurethane foam is often used to make lightweight props and ornaments.Polyurethane rubber.Learn more about movies here: https://brainly.com/question/15738857
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Questions
1 Explain why a solid expands when it is heated.
2 Explain how the liquid in a thermometer changes so that it can be used to
measure a temperature.
3 Use particle theory to explain why solids and liquids cannot be compressed
(squashed into a smaller volume).
4 Use particle theory to explain why liquids and gases can flow.
Answer:
answer of question 1 is
Explanation:
solids are denser than liquid and gases because solid particles are closely packed and do not have any empty spaces between their particels so when solid will heated its particles will spread and there will have more spaces between them so a solid expand on heating.
how to unscramble dtneinreigs
Answer:
Ingredients OR tenderising
Explanation:
convert 0.5 seconds to milliseconds and .02 km to meters
Answer:
0,5 seconds = 500 millisecondes
2 km = 200 meters
Explanation:
Hi can someone help me with completing the word equation and writing a balanced chemical equation with state symbols
Answer:
Sodium hydroxide + ammonium chloride — Sodium chloride + ammonia gas + water
Explanation:
NaOH + NH4Cl — NaCl + NH3 + H2O
When are these words used?
could ,would and should
what's difference between them?
Make 3 sentences using each word
a sentence for 'could': could u pass me the salt?
a sentence for 'would': what would you do if u were the president of usa?
sentence for 'should': you should practise ur spellings before the exam. :)
hope this helps!
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:
HELPPPP Name the three states of matter. Describe the arrangement and movement of atoms in a substance for each state.
Solid, Liquid, and Gas
Solid is the state in which matter maintains a fixed volume and shape; liquid is the state in which matter adapts to the shape of its container but varies only slightly in volume; and gas is the state in which matter expands to occupy the volume and shape of its container.
The states of matter are solid, liquid, and gas. Solid is the state in which matter maintains a fixed volume and shape; liquid is the state in which matter adjusts to the shape of its container but tends to vary only mildly in volume; and gas is the state in which matter expands to occupy the volume and shape of its container.
What is matter?Matter would be any substance with mass and volume that occupies space.
Matter exists in three states: solid, liquid, and gas. The states of matter are solid, liquid, and gas.
Solid is the phase in which matter retains a fixed volume and shape.Liquid is the entity in which matter adjusts to the shape of its container but tends to vary only slightly in volume.Gas is the phase in which matter expands to occupy the volume and shape of its container.Thus, above-mentioned are the three states of matter.
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Which term is defined as “anything that has mass and occupies space”? a -compound b - element c - substance d - matter
Answer:
D) Matter
Explanation:
A sample of copper is heated to 100°C and placed into a calorimeter containing 50 g of water at 25°C after a few minutes the final temperature of the system reaches 40°C how much heat in joules was released by the copper Sample
Answer:
Heat = 3138J
Explanation:
In the system, the sample of Copper is releasing heat that produce the increasing in the temperature of water.
Using the equation of calorimeter, we can find the heat released for the sample of copper (The same that is absorbed for the water):
Q = C×m×ΔT
Where Q is heat, C is specific heat (For water: 4.184J/molK), m is the mass of water (50g) and ΔT is change in temperature of water (40°C-25°C = 15°C)
Replacing:
Q = 4.184J/molK×50g×15°C
Q = 3138J is the heat released for the sample of Copper (The same absorbed for the water).
Answer:
heat=3138j
Explanation:
In the system, the sample of Copper is releasing heat that produce the increasing in the temperature of water.
Using the equation of calorimeter, we can find the heat released for the sample of copper (The same that is absorbed for the water):
Q = C×m×ΔT
Where Q is heat, C is specific heat (For water: 4.184J/molK), m is the mass of water (50g) and ΔT is change in temperature of water (40°C-25°C = 15°C)
Replacing:
Q = 4.184J/molK×50g×15°C
Q = 3138J is the heat released for the sample of Copper (The same absorbed for the water).
A turtle moves at a speed of 1.0km/h. How fast is the turtle moving in meter per second
Answer:
The speed of the turtle is 9.41 centimeters per second.
Explanation:
Speed of small turtle = 566 furlong/fortnight
1 furlong = 20,116.8 cm
1 fortnight = 1,209,600 seconds
Speed of small turtle in centimeter per seconds:
The speed of the turtle is 9.41 centimeters per second.
Explanation:
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
Is iodine a atom,a molecule,an ion or a formule unit?
Answer:
It's an atom
Explanation:
It can't be a molecule since it's only one element, the ion would've been Iodide (I-), and it's not a formula
which of the following molecules would you expect to be optically active
1. CCl2F2
2. 2-methyl butane
3. butan-2-ol
Answer:
waaaaaaaaaaqwwwwwwwwwwww
How can you use the scientific method in everyday life?
You can use the scientific method everyday by asking questions and doing experiments. For example, you want to know how a fire starts, so you do an experiment with it!
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
Explain how the energy of a toy car is transformed as it slides down a ramp. Give evidence that the energy of the car remains the same at all points on the ramp. (30 points)
Answer:
As the car starts to slide down the ramp, it is kinetic energy and when it's on the top of the ramp, it is potential energy. We can see that the energy is now being transferred through the car and ramp.
Explain how the atomic theory was modified from Dalton’s theory to Rutherford’s. Include an explanation of why the theory was modified
Answer:
Thomson's results showed that atoms contain smaller particles, so Dalton's theory had to be modified. Rutherford's results showed that most of an atom is empty space and that the mass is concentrated in the center of the atom.
Explanation:
( like and follow if it helps >W< )
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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name Two soft metals which can be cut with a knife.
Answer:
lithium, and sodium can be cut with a knife
Balance the equation: "Sodium oxide reacts with water to form sodium hydroxide and hydrogen." I can't find the correct coefficients to balance the equation. I have written my unbalanced equation in the file attached.
Answer:
So, sodium oxide + water = sodium hydroxide + hydrogen is written Na2O+H2O-->NaOH+H.
To balance the equation it should read NaO+H2O-->2NaOH
Explanation:
Na2O+H2O-->2NaOH+0H2.......the 0H2 is dropped because there is no value
The correct balance of equation will be
Na2O + H2O - - > 2NaOH
What is a balanced chemical equation?A chemical equation where the number of atoms on both the reactant side and the product side of the reaction are equal is called a balanced chemical equation.
In a balanced chemical equation, not only the number of atoms but the charge and the mass is the same on both sides of the equation.
A chemical equation needs to be balanced to validate the law of conservation of mass. The law of conservation of mass states that the 'mass can neither be created nor destroyed in a chemical reaction'.
If the chemical equation is not balanced, it will go against the fundamental law of law of conservation of mass.
Thus, the chemical equations need to be balanced.
Therefore to balanced the given chemical equation, we equate the number of atoms on both the reactant and the product side of the reaction.
It will be written as
Na2O + H2O - - > 2NaOH
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Which one of these is most likely to gain electrons and which one is most likely to lose electrons? (And please explain why)
1. Ra (Radium)
2. In (Indium)
3. P (Phosphorus)
4. Te (Tellurium)
5. Br (Bromine)
6. Rb (Rubidium)
Answer:
(I). The most likely to lose electron is Rubidium
(II). The most likely to lose electron is Bromine
Explanation:
Given that,
Radium, Indium, Phosphorus, Tellurium, Bromine and Rubidium
We know that,
Metal :
They atom which to lose electron these is called metal.
When the atom loses the electron then the positive charge come on the atom.
The most likely to lose electron is Rubidium
Non metal :
They atome which is gains electron. It is called non metal.
So, we can say that, the non metal gains electron.
When the atom gains the electron then the negative charge come on the atom.
The most likely to gain electron is Bromine
Hence, This is required answer.
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
Consider the reaction of 2.5 grams of Li (s) reacting with 0.5 grams of N2 (g) to produce Li3N (s). A) How many total grams of Li3 N (s) would be produced? B) Which of the starting elements is the limiting reagent, and how many grams of the non-limiting reagent remain after the reaction has completed?
Answer:
A) The amount in grams of Li₃N produced is 1.243 g
B) N₂, is the limiting reagent
The mass of the non-limiting reagent, Li, remaining after the reaction is completed is 1.757 g
Explanation:
The given parameters are;
The mass of Li(s) = 2.5 grams
The mass of N₂ (g) = 0.5 grams
The chemical equation for the reaction can be presented as follows;
6 Li (s) + N₂ (g) → 2 Li₃N
Therefore, 6 moles of Li reacts with 1 mole of N₂ to produce 2 moles of Li₃N
The molar mass of Li = 6.941 g/mol
The molar mass of N₂ = 28.0134 g/mol
The number of moles of a reactant or product, n is given by the relation;
n = Mass of substance/(Molar mass of the substance)
For lithium, Li, n = 2.5/6.941 = 0.3602 moles
For Nitrogen gas, N₂, n = 0.5/28.0134 = 0.01785 moles
A) Given that 1 mole of N₂ to produces 2 moles of Li₃N
0.01785 moles of N₂ will produces 2×0.01785 = 0.0357 moles of Li₃N
The molar mass of Li₃N = 34.83 g/mol
The mass of Li₃N = 34.83 g/mol × 0.0357 moles = 1.243 g
B) 6 moles of Li reacts with 1 mole of N₂ to produce 2 moles of Li₃N
0.3602 moles will reacts with 1/6×0.3602 = 0.06003 mole of N₂
Therefore, N₂, is the limiting reagent and we have;
0.01785 moles of N₂ will react with 6×0.01785 = 0.1071 moles of Li
The number of of moles of Li left = 0.3602 - 0.1071 =0.2531 moles
The mass of lithium left = 0.2531 moles × 6.941 g/mol = 1.757 g
The mass of lithium remaining after the reaction is completed = 1.757 g.
Other than carbon's ability to form four covalent bonds, what is another reason that carbon can form so many compounds? its small size the ability to change shape the ability to form a diatomic molecule the ability to split its electrons
Answer: its small size
Explanation:
