Baking soda, NaHCO3, can be commercially produced during a series of chemical reactions called the Solvay process. In this process, NH3(aq), NaCl(aq), and
other chemicals are used to produce NaHCO3(s) and NH Cl(aq).
To reduce production costs, NH3(aq) is recovered from NHCl(aq) through a different series of reactions. This series of reactions can be summarized by the
overall reaction represented by the unbalanced equation below.
NHACH(aq) + Ca(s) - NH3(aq) + H20() + CaCl(aq)
Balance the equation below for the overall reaction used to recover NH3(aq), using the smallest whole-number coefficients.

Answers

Answer 1

Answer:

CaO(s) + 2NH4Cl(aq) -------> CaCl2(aq) + H2O(l) + 2NH3(g)

Explanation:

The solvay process is an important process in the chemical industry. In this process, ammonia gas is first dissolved in concentrated brine to form a mixture known as ammoniacal brine. This solution is made to trickle down the tower. A counter stream of carbon dioxide is forced up the tower. The two substances react to form sodium hydrogen trioxocarbonate IV. This substance is only slightly soluble and separates out as a solid sludge. The product is now dried and heated to give sodium trioxocarbonate IV.

The overall reaction of the process can be given as;

CaO(s) + 2NH4Cl(aq) -------> CaCl2(aq) + H2O(l) + 2NH3(g)

Calcium chloride is merely a by-product.

Answer 2

Answer:

Based on Reference Table F, which solution will contain the highest concentration of

iodide ions?

A

lead iodide

silver iodide

mercury (II) iodide

iron (11) iodide


Related Questions

When 100 g of 20°C water is mixed with 50 g of 50°C water in a closed system, what is the final water

temperature?

A 20°C

B) 30°C

C) 35°C

D50°C

Answers

The answer is letter B

The final temperature of a mixture of 100g of water at 20°C and 50g of water at 50°C is 30°C.

What is the principle of method of mixtures ?

The amount of heat lost by the hotter sample = The amount of heat gained by the cooler water sample

The amount of heat gained by the cooler water sample is: -

Q1₁= m₁c(T – T₁)

The amount of heat lost by the hotter water sample is: -

Q₂ = m₂c(T₂ - T)

Q₁ = Q₂

m₁c(T – T₁) = m₂c(T₂ - T)

T = (m₁T₁ + m₂T₂)/(m₁+ m₂)

Let the final temperature of the mixture of 100g of water at 20°C and 50g of water at 50°C be T.

m₁ = 100g

T₁ = 20°C

m₂ = 50g

T₂ = 50°C

The final temperature of water = (100*20+50*50)/(100+50)

= (2000+2500)/(150)

=4500/150

=30°C

Therefore , the final temperature of a mixture of 100g of water at 20°C and 50g of water at 50°C is 30°C.

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Calculate the molar mass of the following compounds in g/mol.
CH3CO2H

Answers

Answer:

60g/mol

Explanation:

By using nucleon numbers given on the periodic table, the mass of 1 mole of each element is:

C= 12g

H= 1g

O= 16g

Since molar mass is the sum of the masses of each element present in the compound,

Molar Mass (Mr) = 12+3(1)+12+16(2)+1 = 60g/mol

4. What is the name of A13+?
A)Aluminum ion
B)Aluminum
C)Aluminous ion
D)Aluminide ion

Answers

Answer:

Aluminum ion

Explanation:

I used Google tbh but it has a higher charge then a regular Aluminum atom

Aluminide Ion

I think it’s the right answer

If 11 moles of A are combined with 16 moles of B and the reaction occurs to the greatest extent possible, how many moles of C form?

Answers

it would be 7.3 mol c

Neutrons are in the nucleus of the atom. A neutron has
a) A positive charge
b) No charge
c) A negative charge
d) Twice as much positive charge as a proton

Answers

Answer: B. (No charge)

Explanation:

Protons have a positive charge, electrons have a negative charge.

Neutrons are neutral and therefore have no change.

The use of nuclear energy can have both positive and negative consequences. Which of the following is a positive consequence of using nuclear energy? a. Nuclear energy uses nonrenewable resources. b. Nuclear energy produces little air pollution. c. Uranium ore used for nuclear power plants must be mined and processed. d. Nuclear energy has no environmental impact. Please select the best answer from the choices provided A B C D

Answers

Answer

its B

Explanation:

B.

Nuclear energy produces little air pollution.

When there is unequal sharing between two atoms of the electrons in a bond, which
type of bond is it?

Answers

Answer:

polar covalent bond

Explanation:

How many moles of zinch oxide can be produced from 275 of zinc?

Answers

Answer:

[tex]\large \boxed{\text{4.21 mol}}[/tex]

Explanation:

We must do the conversions :

mass of Zn ⟶ moles of Zn ⟶ moles of ZnO

We will need a chemical equation with masses and molar masses, so, let's gather all the information in one place.

Mᵣ:     65.38

              Zn + … ⟶ ZnO  + …

m/g:   275

(a) Moles of Zn

[tex]\text{Moles of Zn} = \text{275 g Zn}\times \dfrac{\text{1 mol Zn}}{\text{65.38 g Zn}} = \text{4.206 mol Zn}[/tex]

(b) Moles of ZnO

The molar ratio is 1 mol ZnO:1 mol Zn

[tex]\text{Moles of ZnO} =\text{4.206 mol Zn} \times \dfrac{\text{1 mol ZnO}}{\text{1 mol Zn}} = \text{4.21 mol ZnO}\\\\\text{The reaction produces $\large \boxed{\textbf{4.21 mol}}$ of ZnO}[/tex]

Molybdenum metal requires a photon with a minimum frequency of 1.09x1015s-1before it can emit an electron via the photoelectric effect.

a) What is the minimum energy needed to eject an electron?

b)What wavelength of radiation (in nm) will provide a photon of this energy?

c)How many electrons can be freed by a burst of radiation whose total energy is 1.00 μJ, assuming one photon causes one electron to be freed? (μ= micro = 10-6)

d) If molybdenum is irradiated with light of 122nm, what is the maximum kinetic energy of the emitted electrons?

Answers

Answer:

a) 7.22 × 10⁻¹⁹ J; b) 275 nm; c) 1.38× 10¹² electrons; d) 9.1 × 10⁻¹⁹ J

Explanation:

a) Minimum energy to eject photon

E = hf = 6.626× 10⁻³⁴ J·s × 1.09 × 10¹⁵ s⁻¹ = 7.22 × 10⁻¹⁹ J

b) Wavelength required

fλ = c

[tex]\lambda = \dfrac{c}{f } = \dfrac{2.998 \times 10^{8}\text{ m/s}}{1.09 \times 10^{15}\text{/s}} = 2.75 \times 10^{-7} \text{ m} = \textbf{275 nm}[/tex]

c) Electrons required

[tex]\text{No. of electrons} = 1.00 \times 10^{-6}\text{ J} \times \dfrac{\text{1 electron}}{7.22 \times 10^{-19}\text{ J}} = 1.38 \times 10^{12}\text{ electrons}[/tex]

d) Kinetic energy of electrons

a) Energy of photon

[tex]E = hf = \dfrac{\text{hc}}{\lambda} = \dfrac{6.626 \times 10^{-34} \text{ J$\cdot$ s}\times 2.998 \times 10^{8} \text{ m/s}}{122 \times 10^{-9}\text{ m}}= 1.63 \times 10^{-18} \text{ J}[/tex]

b) Maximum kinetic energy

The equation for the photoelectric effect is

hf = φ + KE, where  

φ = the work function of the metal — the minimum energy needed to eject an electron

KE = hf - φ = 1.63× 10⁻¹⁸ J - 7.22× 10⁻¹⁹ J = 9.1 × 10⁻¹⁹ J  

a. The energy of molybdenum to eject electron has been [tex]\rm \bold{7.22\;\times\;10^{-19}}\;J[/tex].

b. The wavelength of the radiation has been 275 nm.

c. The number of electrons present in [tex]\rm 1\;\mu J[/tex] energy has been [tex]\rm \bold{1.38\;\times\;10^1^2}[/tex].

d. The kinetic energy of the emitted electrons as been [tex]\rm \bold{9.1\;\times\;10^-^1^9\;J}[/tex].

The metal emits the energy when it returns from the excited state to ground state.

a. The energy (E) to eject electron has been given by:

[tex]E=h\nu[/tex]

Where, the value of constant, [tex]h=6.626\;\times\;10^{-34}\;\rm J.s[/tex]

The value of frequency has been given, [tex]\nu=\rm 1.09\;\times\;10^{15}\;s^{-1}[/tex]

Substituting the values for energy:

[tex]E=6.626\;\times\;10^{-34}\;\times\;1.09\;\times\;10^{15} \rm J\\\textit E=7.22\;\times\;10^{-19}\;J[/tex]

The energy of molybdenum to eject electron has been [tex]\rm \bold{7.22\;\times\;10^{-19}}\;J[/tex].

b. The wavelength ([tex]\lambda[/tex]) of the radiation has been given by:

[tex]\lambda=\dfrac{c}{\nu}[/tex]

Where, the speed of light, [tex]c=3\;\times\;\rm m/s[/tex]

The frequency has been given as, [tex]\nu=1.09\;\times\;10^{15}\;\rm s^-^1[/tex].

Substituting the values for wavelength:

[tex]\lambda=\dfrac{3\;\times\;10^8}{1.09\;\times\;10^{15}}\;\rm m\\ \lambda=2.75\;\times\;10^-^7\;m\\\lambda=275\;nm[/tex]

The wavelength of the radiation has been 275 nm.

c. The electrons ([tex]e^-[/tex]) burst out can be given as:

[tex]e^-=\dfrac{E}{E'}[/tex]

Where, the energy of radiations, [tex]E=1\;\times\;10^{-6}\;\rm J[/tex]

The energy of each electron has been calculated as, [tex]E'=7.22\;\times\;10^{-19}\;\rm J[/tex]

Substituting the values for number of electrons:

[tex]e^-=\dfrac{1\;\times\;10^-^6}{7.22\;\times\;10^-^1^9} \\e^-=1.38\;\times\;10^1^2[/tex]

The number of electrons present in [tex]\rm 1\;\mu J[/tex] energy has been [tex]\rm \bold{1.38\;\times\;10^1^2}[/tex].

d. The maximum kinetic energy (K.E.) of the radiation has been given as:

[tex]K.E.=\dfrac{hc}{\lambda} -E^'[/tex]

Where, the value of constant, [tex]h=6.626\;\times\;10^{-34}\;\rm J.s[/tex]

The speed of light, [tex]c=3\;\times\;\rm m/s[/tex]

The wavelength of the radiation, [tex]\lambda=122\;\times\;10^-^9\;\rm m[/tex]

Energy of each electron, [tex]E'=7.22\;\times\;10^{-19}\;\rm J[/tex]

Substituting the values, for kinetic energy:

[tex]K.E.=\dfrac{6.626\;\times\;10^{-34}\;\times\;3.0\;\times\;10^8}{122\;\times\;10^-^9}\;-\;7.22\;\times\;10^-^1^9\;\rm J \\\textit {K.E.}=9.1\;\times\;10^{-19}\;J[/tex]

The kinetic energy of the emitted electrons as been [tex]\rm \bold{9.1\;\times\;10^-^1^9\;J}[/tex].

For more information about photoelectric effect, refer to the link:

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What is the best example of electromagnetic energy in everyday life

Answers

Electromagnetic Radiation. Do you listen to the radio, watch TV, or use a microwave oven? All these devices make use of electromagnetic waves. Radio waves, microwaves, visible light, and x rays are all examples of electromagnetic waves that differ from each other in wavelength.

Answer:best

Explanation:

Best

Which molecule is an alkyne?
A. 2-ethylhexane
B. 2-nonyne
C. trans-2-pentene
D. Pentane

Answers

Answer:Ethyne

Explanation:

Ethyne is more commonly known under the trivial name acetylene. It is the simplest of the alkynes, consisting of two carbon atoms connected by a triple bond, leaving each carbon able to bond to one hydrogen atom. Since both carbon atoms are linear in shape, all four atoms lie in a straight line.

2-nonyne molecule is an alkyne. Hence, option B is correct.

What is alkyne?

Alkynes are groups of hydrocarbons that have the general formula of {Cn H2n - 2}. They have a triple carbon-to-carbon bond (C≡C) in their structure. Ethyne (HC≡CH) is the first member of the alkyne series.

Ethyne is more commonly known under the trivial name acetylene. It is the simplest of the alkynes, consisting of two carbon atoms connected by a triple bond, leaving each carbon able to bond to one hydrogen atom.

Since both carbon atoms are linear in shape, all four atoms lie in a straight line.

Hence, option B is correct.

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What is thought to be another cause of the large size of our brain compared to chimpanzees?

Answers

Answer:

Compared to early humans our brains seemed to have increased in size, and part of the cause may be because of things like Climage change, ecology and social competition

Explanation:

2 in the bone it lab own

how many grams of H20 will be produced by 18g H2

Answers

Answer:

160.86 g to the nearest hundredth.

Explanation:

H2 + O  ---> H2O

2.016 g H2 produces 18.016 g H2O

1g      ..    ..   ..   ..   ..    18.016 / 2.016 g H2O

18g   ..   ..   ..  ..  .. . .     (18.016 * 18) / 2.016 g H2O.

= 160.86 g.

A sample of octane undergoes combustion according to the equation 2 C8H18 + 25 O2 → 16 CO2 + 18 H2O ΔH°rxn = -11018 kJ. What mass of O2 (in grams) must react in order to generate 7280 kJ of energy?

Answers

Answer:

[tex]\large \boxed{\text{528.7 g} }[/tex]

Explanation:

It often helps to write the heat as if it were a reactant or a product in the thermochemical equation.

Then you can consider it to be 11018 "moles" of "kJ"  

We will need a chemical equation with masses and molar masses, so, let's gather all the information in one place.

M_r:                      32.00

              2C₈H₁₈ + 25O₂ ⟶ 16CO₂ + 8H₂O + 11 018 kJ

n/mol:                                                                  7280

1. Moles of O₂

The molar ratio is 25 mol O₂:11 018 kJ

[tex]\text{Moles of O}_{2} = \text{7280 kJ} \times \dfrac{\text{25 mol O}_{2}}{\text{11 018 kJ}} = \text{16.52 mol O}_{2}[/tex]

2. Mass of O₂

[tex]\text{Mass of C$_{8}$H}_{18} = \text{16.52 mol O}_{2} \times \dfrac{\text{32.00 g O}_{2}}{\text{1 mol O}_{2}} = \textbf{528.6 g O}_{2}\\\text{The reaction requires $\large \boxed{\textbf{528.67 g O}_{2}}$}[/tex]

PLEASE HELP ME OUTTTT

How many grams of Fe3O4 are required to react completely with 54.29 grams of H2?

Fe3O4 + H2 → Fe + H2O

Answers

Answer:

Balance the equation

Fe3O4 + 4H2---> 3Fe +4H2O

Molar mass H2=(2*1)=2g/mol

Mass of H2=54.29grams

mole of H2= 54.29/2=27.15mol

4 mol of H2 = 1 mol Fe3O4

27.15mol of H2= 6.79mol of Fe3O4

Moles of Fe3O4 =6.79mol

Molar mass of Fe3O4= (56×3)+(16×4)

=168+64=232g/mol

Grams of Fe3O4 required to react with 54.29 grams of H2 is 232g/mol× 6.79mol

=1575.28g

hey so for science class im making a brochure for a vacation to mars.
can someone give me a good name and theme for a hotel that would be on mars?

Answers

Answer:

The name of the hotel can be the Red dust hotel. And the theme could red and rocky

Explanation:

explain how redox reactions are the source of electron flow in batteries. how can a dead battery be said to have attained equilibrium?

Answers

Answer:

can u help me whith one of my qutions

Explanation:

What happens at the particle level during a chemical reaction?

Answers

Answer:

Reactants contact each other, bonds between atoms in the reactants are broken, and atoms rearrange and form new bonds to make the products.RT

Explanation:

Match each element to its electron dot diagram. The symbol X represents the element. Refer to the periodic table if needed. fluorine sodium phosphorus magnesium One of the X's didn't work, but it had 2 dots on top, 2 on the right, 2 on the bottom, and 1 on the left.

Answers

Answer:

The atom with one outer most electron is sodium

The atom with two outermost electrons is magnesium

The atom with five outermost electrons is phosphorus

Explanation:

A dot structure of an atom shows the number of electrons present on the outermost shell of that atom. In order words, a dot structure shows the valence electrons present on the valence shell of an atom.

Sodium has an atomic number of 11, hence the electrons are arranged in three shells in the following order 2,8,1. This implies that one electron is present on it's outermost shell.

Magnesium has an atomic number of 12. Its electrons are arranged in shells in the order; 2,8,2. Hence, two electrons are present in its outermost shell.

Phosphorus contains 15 electrons(atomic number of 15), these electrons are arranged in shells in the order 2,8,5. Hence there are five outermost electrons present in phosphorus.

Answer:

1 dot sodium

2 dots Magnesium

7 dot Fluorine

5 dot Phosphorus

Explanation:

review the types of elements that create ionic bonds as
well as the types of elements that create covalent bonds.
• N2 • CCl4 • SiO2
• AlCl3 • CaCl2 • LiBr

Answers

Answer:

N2 Covalent

CCl4 Covalent

SiO2 Covalent

AlCl3 Covalent

CaCl2 Ionic

LiBr Covalent

Explanation:

With covalent bonds, there is a sharing of electron pairs between the atoms.

With ionic bonds, there is complete transfer of valence electrons between atoms. Formed by the interaction of a metal with a non-metal.

Where:

Electrons aren't transferred in covalent bonds.

Protons aren't  transferred in covalent bonds

Protons aren't shared in covalent bonds

N3-

C4+

Cl-

Si4+ = Metal

O2- = Non-metal

Al3+ = Metal

Li+ = Metal

Ca2+ = Metal

Br  1-, 1+, 5+ = Halogen

N2 = N3- and N3- Covalent

CCl4 = C4+ and Cl- x4 Covalent

SiO2 = Si4+ and O2- x 2 Metal with non metal Covalent

AlCl3 = Al3+ and Cl- x 3 Covalent Though this one is complex as to why because it seems like it should be ionic

CaCl2 = Ca2+ and Cl- x 2 Metal with non-metal Ionic

LiBr = Li+ and Br- Covalent as neither is a non-metal

Ava’s best friend has an indoor cat. Ava notices that she sneezes every time that she visits her friend. Ava suspects that she is allergic to cats but is unsure. What is the best thing for Ava to do next?

Answers

the best thing for her to do next is go get an allergy test from the doctors to see if she’s allergic.

C) Test her suspicion by going to see an allergist to diagnose the allergy.

It's right

What does the law of conservation of matter show?
A. That the total number of atoms in matter will never change.
B. That matter can never change form.
C. That atoms will combine in the simplest possible arrangement.
D. That atoms in matter can never be rearranged.

Answers

Answer: A) That the total number of atoms in matter will never change.

Explanation: Matter cannot be destroyed nor created. Matter is made up of atoms. The amount of atoms in an object will never change, even when changed into a different form.

Ex. When ice cubes melt there is still the same amount of water just in a different form.

Answer:

A

Explanation:

Help!!
Which of the following is a chemical reaction?

a. New atoms are formed when substances are mixed together
b. A solid material melts and becomes a liquid
c. Atoms of the reactants rearrange to form a new substance

Answers

Answer:

C-Atoms of the reactants rearrange to form a new substance

Explanation:

Answer:

The answer is A.

Explanation:

B. is called a physical reaction

And C. is just a rearrangement.

what are the steps to go from the names of compounds to the formulas

Answers

Answer:

Explanation:

write down the formulas, use the expressions and formulas to convert

calculate the amount of I - 125 that remains after 178.2 days if we started with 300 grams.

Answers

Answer:

38.3 g

Explanation:

The half life of a substance is the time taken for the substance to decay to about half of its amount.

Let us assume that I-125 have a half life of 60 days. It means that every 60 days, the amount of I - 125 would be halved.

The amount of I - 125 (A) that remains after t days is given by:

[tex]A=A_o*\frac{1}{2^n} \\[/tex]

Where Ao is the initial amount and n = t / half life

Given that:

Ao = 300 g, t = 178.2 days.

Therefore n = t / half life = 178.2 days / 60 days = 2.97

[tex]A=A_o*\frac{1}{2^n} \\A=300*\frac{1}{2^{2.97}}\\ A=38.3\ g[/tex]

Water boils at 100°C at sea level. If the water in this experiment did not boil at 100°C, what could be the reason?

Answers

One reason could be that the water in this experiment, didn’t boil, but instead became a “chemical reaction” from atmospheric pressure which is normal.

While heating two different samples, of
sea level water it decides on a temperature of 102°C and the other boils at 99.2°C. Basically calculating of the percent error.

TRUE OR FALSE

As the human population increases, demand for natural resources will also increase.

Answers

It’s true, as the human population grows, our consumption of natural recorded increases

The bridge over the river has a weight limit of 12.65 tons to cross it. The truck weighs 10.89 tons. How many tons is the truck under the weight limit

Answers

Answer:

It is 1.76 tons under the weight limit.

Explanation:

12.65

-10.89

= 1.76

What is a chemical equation?
A. a substance
B. a shorthand representation of a chemical reaction
C. a shorthand representation of a chemical bond
D. a diatomic molecule

Answers

The correct answer is B

What causes the sun's core and the earth's core to have extremely high temperatures?
Select one:
a. The sun undergoes fusion and the earth undergoes fission. b. Both have nuclear fusion occurring in their cores.
c. Both have nuclear fission occurring in their cores.
d. The sun undergoes fission and the earth undergoes fusion.

Answers

(a) The sun undergoes fusion while the earth undergoes fission.
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