Explain why warm nitric (V) acid is used in preparation of lead carbonate ​

Answers

Answer 1
The direct addition of dil. Sulphuric acid to lead carbonate will cause the deposition of lead sulphate on the surface of lead carbonate which stops further reaction on it.So even though chemically it is correct,practically we can add sulphuric acid to lead carbonate to prepare lead sulphate.

Related Questions

what effect does a catalyst have on the energy of a reaction system

Answers

answer : A catalyst speeds up the rate of a reaction.

What is the final temperature of a 300.0 gram glass of water if it is placed
in the microwave at 22.0°C and it absorbs 5000.0 joules of energy?

Answers

The final temperature of a 300.0-gram glass of water if it is placed

in the microwave at 22.0°C and it absorbs 5000.0 joules of energy is

3.987°C.

What does ' amount of heat gained or lost " means?

The equation q = MCT, where m is the mass of the sample, c is the specific heat, and T is the temperature change, can be used to determine the amount of heat that a sample (q) gains or loses. q = mct. liquid mass, m (so this would be in grams) t = temperature change. For example, water's particular constant, C, is 4.2 J g-1 K-1, therefore you just enter that value into the formula in the exam to get the energy of water.

Calculating heat energy involves using the equation Q = MCT. Mass, specific heat, and temperature change are all components of heat energy. Q = MCT. where Q is the heat energy, M is the material's mass, C is the specific heat, and T is the temperature change.

  q =  m CΔT

5000 J = 300 g × 4.18 J × ΔT

ΔT = 5000/1254

= 3.9872

= 3.987°C.

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A typical car battery in a car is filled with a solution of sulferic acid, which is approximately 39.9% sulfuric acid. If the density of this
solution is 1.3 g/mL, determine the number of grams present in 500.0mL of battery solution.

Answers

This tells you that the reaction will always consume 2 times more moles of lithium hydroxide than moles of sulfuric acid.

Explanation of  Sulfuric Acid?The balanced chemical equation can be used to help you figure out how many moles of each reactant must be present in solution in order for complete neutralization to occur when it comes to neutralization reactionH2SO4(aq]+ 2LiOH(aq]→ Li2SO4(aq]+ 2H2O(l]Lithium hydroxide and sulfuric acid have a 2 mole ratio. You can infer from this that the reaction will always consume.Lithium hydroxide has twice the moles of sulfuric acid.

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does anyone know how to answer this question?

Answers

The answer is B. You first subtract the accepted value from the experimental value and then divide that answer by the accepted value. At the end you multiply by 100 to get the percent error.

Click oil basics to explore the natural resources needed for the production of plastics. use the information to answer the question. which of these ingredients is important in making plastics? carbon dioxide particulate matter natural gas volatile organic compounds

Answers

The correct answer is option C: natural gas

The ingredient which is important in making plastics is natural gas.

Plastics are the refined form of natural gas, plant liquids, and crude oils.

Plastics can be manufactured in two ways: synthetic and biobased.

Synthetic plastics come from raw materials including natural gas, crude oil, and coal.

On the contrary, biobased plastics are manufactured from renewable materials such as starch, vegetable fats, oils, and carbohydrates.

However, the most common method of plastic manufacturing is the transformation of raw materials into refined propane and ethane.

In the next step, ethane and propane undergo cracking which transforms them into ethylene and propylene which are the building blocks of long chains of polymers.

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Answer:it's C

Explanation:

I just did it on Edge you're welcome Happy early Halloween you're beautiful and have a nice day. :)

PLEASE HELP HALF MY GRADE!!What is a procedure you can follow to find evidence that yeast and plant cells produce carbon dioxide
during cellular respiration?

Answers

Answer:

Cellular respiration is the process where cells break down glucose and then they convert it into energy. Cellular respiration is important because without cellular respiration there would not be any energy and without energy there would not be any food.

What is the force that holds a pencil down against a desk?
Responses

friction


momentum

gravity


normal

Answers

Answer:

Gravity

Explanation:

Gravity is the force that attracts a body towards the centre of the earth, or towards any other physical body having mass.

Answer:

Gravity

Explanation:

Gravity is the force that attracts a person or an object to weigh, or pull. I hope this helped :)

is it true that the physical constants of abuse substance depend on the mass of the sample used​

Answers

No, the physical constants of abuse substance do not depend on the mass of the sample used​.

Does mass have an impact on density?

Mass and volume are intimately correlated with density. In reality, it explains the precise nature of the connection between the two. By dividing the mass of an object by its volume, we may get its density. The mass is considered to have a low density if it has a high volume but a tiny mass.

By dividing a material's mass by its volume, one can get a material's density, which is defined as its mass per unit volume. Returning to the molecular level, the mass of a material's molecules and how tightly they are packed together determine the material's density.

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Zinc metal reacts with yellow crystals of sulfur in a fiery reaction to produce a white powder of zine sulfide. A chemist determines that 65.4 g zinc reacts with 32.1 g of sulfur. How many grams of zinc sulfide are produced?​

Answers

Answer:

Explanation:

Zn + S ---> ZnS

Mass of Zinc + Mass of Sulphur = Mass of Zinc sulfide ( Law of conservation)

Mass of zinc= 65.4g

Mass of Sulfur =  32.1g

Mass of Zinc Sulfide= (65.4 + 32.1)g

Mass of Zinc Sulfide = 97.5g

In each pair below, circle the particle which you believe is larger and justify your choice in the space
provided.

Lithium Atom or Lithium Common Ion

Fluorine Atom or Fluorine Common Ion

Sodium Common lon or Magnesium Common Ion

Oxide Common lon or
Fluoride Common lon

Answers

Lithium Atom, Fluorine common ion, Magnesium Common ion, Oxide common ion are the ones that are larger in each of the choices as given.

What are cations and anions?

Positively charged ions are known as cations. Negatively charged ions are further referred to as anions. A charged atom or molecule can be referred to as an ion.

A balanced atom will change into a positively charged cation if one or more of its electrons are lost. A balanced atom will change into a negatively charged anion if it gains one or more electrons.

In the formula for an ionic compound, the positive ion, known as a cation, is listed first, followed by the negative ion, known as an anion. The net charge or neutral electrical charge in a balanced formula is zero. A cation can be either positive or negative.

An anion contains more protons than electrons, while a cation has a net positive electrical charge. An anion has a greater number of electrons than protons and a net negative electrical charge.

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pentacarbonyliron (fe(co)5) reacts with phosphorous trifluoride (pf3) and hydrogen, releasing carbon monoxide: fe(co)5 2pf3 h2 → fe(co)2(pf3)2(h)2 3co the reaction of 5.0 mol of fe(co)5, 8.0 mol of pf3 and 6.0 mol of h2 will release mol of co.

Answers

Fe(CO)₅ is the limiting reactant given the provided statement since it has the lowest ratio.

What defines a limiting reactant?

The quantity of product that can be created is constrained by the reagent that is used first in a chemical reaction, also referred to as the limiting reactant (or limiting reagent).

Briefing:

Calculating the moles supplied/moles stoich ratio will reveal the limiting reactant, which is the one with the lowest value.

Fe(CO)₅ ratio = [5 g / 195.9 g/mol] / 1

Fe(CO)⁵ ratio = 0.025

PF3 ratio = [8 g / 87.97 g/mol] / 2

PF3 ratio = 0.045

H2 ratio = [6 g / 2 g/mol] / 1

H2 ratio = 3

We can see that Fe(CO)5 has the lowest ratio, so it is the limiting reactant.

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If the mass of the ice to the cup increases the total energy in the cup will what

Answers

The mass of the ice to the cup increases The total energy in the cup will - The mass remains unchanged.

What is mass?
The total amount of matter in a physical body is defined as its mass. In the presence of a net force, it also serves as a gauge for the body's inertia, or resistance to acceleration (change in velocity). The gravitational pull of an object on other bodies is also influenced by its mass. The kilogramme is the SI's primary mass unit (kg). Even though weight is frequently measured with a spring scale rather than a balancing scale and directly compared to known masses, mass and weight are not the same thing in physics. Because of the lower gravity on the Moon, an object would weigh less while maintaining the same mass as it does on Earth.

The latent heat of fusion is absorbed by the mass. This is required for phase changes.

Despite absorbing heat from the environment, the temperature stays the same as long as there is still some ice present. The warmth that is absorbed is used as latent heat rather than sensible heat.

The mass remains unchanged.

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in a 4.00 l pressure cooker, water is brought to a boil. if the final temperature is 115.0 °c at 3.20 atm, what quantity in moles of steam are in the cooker?

Answers

The no. of moles of steam present in the cooker is 0.402 mol.

The ratio between a substance's given mass in a chemical reaction and the mass of one mole of that material is used to determine how many moles there are of that substance. Any material has an atomic mass of one mole, or 6.023 x [tex]10^{23}[/tex], according to Avogadro. Additionally, No. of moles is employed to represent concentration measurements like mole per liter and molecular weight.

Given:

Pressure, P = 3.20atm

Volume, V = 4L

Temperature, T = 115℃ = 115 + 273 = 388K

To find:

No. of moles, n = ?

Formula:

PV = nRT

Calculations:

n = 3.20 x 4 / 0.082 x 388

n = 0.402 mol

Result:

0.402 moles of steam is present in the cooker.

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When a metal is reduced by reaction with carbon, which element is removed from the compound?

A: Carbon
B: Oxygen
C: Hydrogen
D: Silver

Answers

Answer:

Oxygen

Explanation:

reduction is the removal of oxygen to a substance

what is causing the marshmallow to change their sate of matter

Answers

Answer:

Any form of semi high energy waves cause the water molecules inside the marshmallow to vibrate which heat and soften the sugar matrix inside the marshmallow. The weakened sugar matrix allows air bubbles within the marshmallow to expand rapidly and the marshmallow puffs up and becomes goo. If this proccess is repeated it can completly change it's state of matter.

Explanation:

Find the balanced molecular equation FeSO4(aq) + K3PO4(aq) →

Answers

Answer:

3FeSO4 + 2K3PO4 → Fe3(PO4)2 + 3K2SO4

Explanation:

a sample of an unknown gas effuses in 10.7 min. an equal volume of h2 in the same apparatus under the same conditions effuses in 2.42 min. what is the molar mass of the unknown gas?

Answers

Molar mass of the unknown gas= 39.09 g / mol

T= TIME

MW= MOLAR MASS

MW H₂ = 2

now, Apply graham law--

graham law states that rate of effusion of a gas is inversely proportional to square root of the molar mass of its particle.

Rate1/rate2 = √(MW2/MW1)

T2/T1 =√(MW2/MW1)           (BECAUSE, VOLUME EQUAL)

(10.7/2.42)²= MW2/2

MW2=molar mass of the unknown gas = 2α×(10.7/2.42)²

=39.09 g / mol

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problem b. a silicon crystal is to be grown using the czochralski method. the ingot of crystalline silicon is to contain 3x1015 dopant atoms/cm3. (show your work.) a. if kd

Answers

A small seed crystal is placed into a melt in a crucible and pulled upward to form a single crystal using the Czochralski (CZ) method of crystal formation. The approach was created in 1916 by a Polish scientist by the name of Jan Czochralski.

How is silicon crystallized using the Czochralski CZ method?

The Czochralski method is to be used to create a silicon crystal as the solution to problem B. The crystalline silicon ingot must have 3x1015 dopant atoms per cubic centimeter. (Indicate your work.) a. if kd

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A compound of carbon and hydrogen and oxygen (ethylene glycol- antifreeze) is determined to be 38. 7% C, 51. 6% O, and 9. 7% H. Calculate the molecular formula of the molar mass is 62 g/mol

Answers

The molecular formula of the given is 0.519.

Equation :

To calculate the molecular formula we need a simple formula,

molecular formula = divide the molecular mass / empirical formula

So, the known are

molecular mass = 62 g/mol

empirical formula = CH₃O

C = 38. 7%

H = 9. 7%

O =  51. 6%

empirical formula = 38. 7% + (9. 7% x 3) + 51. 6%

empirical formula = 119.4

Now, putting the values in formula

molecular formula = molecular mass / empirical formula

molecular formula = 62 g/mol / 119.4

molecular formula = 0.519

Hence, the molecular formula is 0.519.

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When a screen is used to easily separate substances, what physical properties are being used?
Responses

temperature, size
temperature, size

size, shape
size, shape

texture, shape
texture, shape

density, buoyancy btw this is science

Answers

When a screen is used to easily separate substances, what physical properties are being used then the size are used

A physical property is a characteristic of matter that is not associated with a change in its chemical composition and similar examples of physical properties include density, color, hardness, melting and boiling points, and electrical conductivity and the physical property that is in use when substances are separated using a screen is differences in particle size of the substances and this is the separation method

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Answer:

d

Explanation:

Help me i have till 5 to get this assignment in ​

Answers

Energies of given waves exists:

6. 17.27 × [tex]10^{-20}[/tex]  J

7. 63.61 × [tex]10^{-23[/tex] J

8. 9.99 × [tex]10^{-24}[/tex] J

9. 41.5 × [tex]10^{-21}[/tex] J

10. 16.89 ×  [tex]10^{-19}[/tex] J

What is the relation of frequency and energy?E = hv is the energy equation. In the formula, E stands for energy, h for Planck's constant (6.626 × 10 -34 J s), and v for frequency. Since frequency rises as energy falls, frequency and energy are related directly in the energy equation.

Energy travels in waves. Their frequency and amplitude both affect how much energy they transport. The amount of energy increases with frequency and amplitude, respectively.

Energy is inversely correlated with wavelength because it is directly proportional to the electromagnetic frequency of the photon. The energy of a photon increases with its frequency. In other words, the energy of a photon decreases with increasing wavelength.

The energies of given waves exists:

6. 17.27 × [tex]10^{-20}[/tex]  J

7. 63.61 × [tex]10^{-23[/tex] J

8. 9.99 × [tex]10^{-24}[/tex] J

9. 41.5 × [tex]10^{-21}[/tex] J

10. 16.89 ×  [tex]10^{-19}[/tex] J

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-) Potassium is also in Group 1 of the periodic table. Potassium reacts with water in a similar
way to lithium. Write down two differences you would see between the reactions of
potassium and lithium with water.

Answers

Lithium react slowly with water while potassium react violently with water. potassium caught  fire while lithium does not caught fire.

What is chemical reaction?

Chemical reaction is defined as a procedure in which one or more compounds, known as reactants, are changed into one or more distinct substances, known as products.

It can also be defined as a process in which two or more molecules collide with the proper orientation and enough force to produce a new product.

There are mainly five types of reaction.

Synthesis reactionAcid base reactionRedox reactionDecomposition reactionPrecipitation reaction

Thus, Lithium react slowly with water while potassium react violently with water. potassium caught  fire while lithium does not caught fire.

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heat is added to a 200.-gram sample of h2o(s) to melt the sample at 0°c. then the resulting h2o( ) is heated to a final temperature of 65°c. 5. compare the amount of heat required to vaporize a 200.-gram sample of h20( ) at its boiling point to the amount of heat required to melt a 200.-gram sample of h2o(s) at its melting point.

Answers

54.418 kJ amount of heat required to completely melt the200gm of H2O sample at its melting point.

What is the calculation of the above problem?

Mass of water = 200 g

Initial temperature of the water = 0°C

Final  temperature of the water = 65°C

Temperature change = Delta T = 65

Specific heat capacity = 4.168J/g C

 (1 kJ = 1000J)

54.418 kJ amount of heat required to completely melt the sample.

At 100 C and 1 atm, how much heat is required for 1 g of water to evaporate?

At 100 °C, which is where water boils, the heat of vaporization for water is around 540 cal/g.

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What would happen if three types of water
are placed in the same container?

Answers

When water is placed in the same container it can cause a growth of bacteria because it will be place in warm area.

A 5.0 Amp current is passed through a solution of copper (II) sulfate for four hours. How many grams of copper could form on the cathode during this process?

Answers

The amount of copper that would be deposited on the cathode during the process is 47.75 g.

What is the amount of copper (II) deposited?

The amount of copper (II) deposited is calculated as follows;

CuSO² ⇄ Cu²⁺  +  SO₄²⁻

Cu²⁺  +  2e⁻  → Cu

.

From the oxidation reaction above, we can infer that,

2F -----------> 64 g of copper (Cu)

where;

F is Faraday = 96500 C

The quantity of charge passed through the solution of  copper (II) sulfate for four hours is calculated as follows;

Q = It

where;

I is the currentt is the time of current flow

Q = (5 A) x (4 hrs x 3600 s/hr)

Q = (5 A) x (14,400 s)

Q = 72,000 C

The amount of copper that will be deposited by this quantity of charge is calculated as follows;

96500 C --------> 64 g

72,000 C ---------> ?

= (72,000 X 64) / 96500

= 47.75 g

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Which sample is composed of particles arranged in a regular geometric pattern?
A) Cl2(g)
B)CCl4(l)
C)LiCl(s)
D)LiCl(aq)

Answers

Solid Lithium chloride (LiCl) is made up of particles arranged in a regular geometric pattern. Therefore, option (C) is correct.

What types of solids have geometric patterns?

In the crystalline Solid, the constituent particles are closer to each other due to the intermolecular force of attraction between them. So there is no free space between them due to which its shape can't be changed which is said to be regular geometry.

The building constituents in crystalline solids, arrange in a regular manner throughout the entire 3D network. The ordered arrangement of constituent units extends over a large distance. Thus, crystalline solids have a long-range arrangement. A crystalline solid contains a large number of units called crystals.

Lithium Chloride is a white solid soluble in water, ether, and alcohol and chemical formula for lithium chloride is LiCl.  Lithium chloride has the same crystal structure as NaCl.

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Please may someone help me with the bottom bit!

Answers

            Precipitate definition (Entry 2 of 3) 1: a substance that has been physically or chemically isolated from a solution or suspension, typically in the form of an insoluble crystalline or amorphous solid. 2: a byproduct, outcome, or result of a procedure or action. adjective. precipitate.

What is an example of precipitate in chemistry?

Precipitation Illustration

        Silver chloride will solidify out of solution when silver nitrate and sodium chloride are combined in water. Silver chloride is the precipitate in this instance.

What does precipitate represent?

       Solids are created by the process of precipitation after two chemicals react. The downword () arrow symbol is used to represent the production of precipitate in this type of reaction.

What two types of precipitate are there?

      It happens between the reactant ions in the aqueous solutions that give rise to the material. Complete response: Precipitation includes the following: snow, sleet, hail, and rain.

What color is precipitate?

       An excess of the light blue precipitate dissolves to create an inky transparent solution. A little amount of sodium hydroxide solution and subsequently an excessive amount are added to solution W. There develops an insoluble white precipitate.

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Object A has a density of 2.6 g/cm³. What is the mass of 36.5 cm³ of object A in units of g

Answers

According to solving the object's mass is 94.9g.

Mass: What is it?

One of the fundamental quantities in physics and the most fundamental aspect of matter is mass. A body's mass is the measurement of the volume of matter it contains. The kilogram serves as the SI unit for mass (kg). This is how the mass formula appears:

Mass is equal to Density x Volume.

How do mass, density, and volume relate to one another?

How much space an object or substance occupies is determined by its volume.

A substance or object's mass is a measure of how much matter it contains. The density of an object or substance is the ratio of its mass to its volume, or the quantity of material it contains (its mass).

According to the question

Object density=2.6g/cm³

volume= 36.5 cm³

Formula :-Mass = Density × Volume

M=2.6g/cm³ ×36.5 cm³

M=94.9g

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calculate the volume in liters of a m potassium dichromate solution that contains of potassium dichromate . be sure your answer has the correct number of significant digits.

Answers

Incomplete question but using assumed values, the volume of m potassium dichromate solution that contains potassium dichromate is 9.1L

To calculate the volume of solution, we use the equation for molarity of solution:

Molarity of solution = mass of solute/molar mass of solute*volume of solution (in liter)

Where assumed values are:

Molarity of solution = 0.15 M

Given mass of potassium dichromate = 400. g

Molar mass of potassium dichromate = 294.15 g/mol

Volume solution in liter = x

i.e.

0.15 = 400/294.15*x

Volume of solution in liter = 400/294.15*0.15

Volume of solution in liter = 400/44.12

Volume of solution in liter = 9.06

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A 1.02 g magnesium supplement contains 25.0% Mg by mass. The magnesium is present in the supplement as MgO(s) (molar mass 40.30 g/mol). How many grams of MgO(s) are in the magnesium supplement? Write your answer using three significant

Answers

Based on the percentage mass of magnesium oxide in the sample, the mass of Magnesium oxide in the sample is 0.42 g.

What is the mass of magnesium in the supplement?

Magnesium is a metallic element with an atomic number of 12.

Magnesium is an important mineral that is used as a supplement s well as in drugs such as milk of magnesia.

Considering the given magnesium supplement:

1.02 g magnesium supplement contains 25.0% Mg by mass.

Magnesium is present in the supplement as magnesium oxide, MgO.

The molar mass of magnesium oxide, MgO = 40.30 g/mol

Molar mass of magnesium = 24.0 g

Percentage mass of Magnesium oxide in the sample = 40.3 / 24 * 25

Percentage mass of Magnesium oxide in the sample = 42%

Mass of Magnesium oxide in the sample = 42 % * 1.02

Mass of Magnesium oxide in the sample = 0.42 g

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