Why does every chemical reaction require a certain amount of activation energy?

9.D

10.A

11.C

12.B

13.D

14.C

15.A

16.A

18.C

Answer:

Unicellular organisms consist of only one cell and multicellular organisms consist of many cell.

Explanation:

Living things made up of a cell are called unicellular beings. They are very small and simple. In other words, unicellular organisms are those that are formed only by a single cell in which all the vital functions necessary for life are produced. For this reason, they are mostly microscopic organisms. Examples of unicellular organisms are viruses or bacteria.

Multicellular organisms are made up of a large number of cells. They present, therefore, a greater complexity than unicellular organisms in terms of the functions they develop. All current multicellular organisms come from a single cell, that is, they begin their life being unicellular. That is, they are formed from a zygote. Some examples of multicellular organisms are mammals, fungi, and mosses.

So, unicellular organisms consist of only one cell and multicellular organisms consist of many cell.

Answer:

Percentage yield of O₂ = 73.4%

Explanation:

We'll begin by writing the balanced equation for the reaction. This is given below:

2KClO₃ —> 2KCl + 3O₂

Next, we shall determine the mass of KClO₃ that decomposed and the mass of O₂ produced from the balanced equation. This can be obtained as follow:

Molar mass of KClO₃ = 39 + 35.5 + (3×16)

= 39 + 35.5 + 48

= 122.5 g/mol

Mass of KClO₃ from the balanced equation = 2 × 122.5 = 245 g

Molar mass of O₂ = 2 × 16 = 32 g/mol

Mass of O₂ from the balanced equation = 3 × 32 = 96 g

SUMMARY:

From the balanced equation above,

245 g of KClO₃ decomposed to produce 96 g of O₂.

Next, we shall determine the theoretical yield of O₂. This can be obtained as follow:

From the balanced equation above,

245 g of KClO₃ decomposed to produce 96 g of O₂.

Therefore, 400 g 245 g of KClO₃ will decompose to produce

= (400 × 96)/245 = 156.7 g of O₂.

Thus, the theoretical yield of O₂ is 156.7 g

Finally, we shall determine the percentage yield of O₂. This can be obtained as follow:

Actual yield of O₂ = 115.0 g

Theoretical yield of O₂ = 156.7 g

Percentage yield of O₂ =?

Percentage yield = Actual yield /Theoretical × 100

Percentage yield = 115/156.7 × 100

Percentage yield = 11500/156.7

Percentage yield of O₂ = 73.4%

Answer:

the reaction is spontaneous

Answer:

1. 0.125 mole

2. 42.5 g

3. 0.61 mole

Explanation:

1. Determination of the number of mole of NaOH.

Mass of NaOH = 5 g

Molar mass of NaOH = 23 + 16 + 1

= 40 g/mol

Mole of NaOH =?

Mole = mass /molar mass

Mole of NaOH = 5/40

Mole NaOH = 0.125 mole

2. Determination of the mass of NH₃.

Mole of NH₃ = 2.5 moles

Molar mass of NH₃ = 14 + (3×1)

= 14 + 3

= 17 g/mol

Mass of NH₃ =?

Mass = mole × molar mass

Mass of NH₃ = 2.5 × 17

Mass of NH₃ = 42.5 g

3. Determination of the number of mole of Ca(NO₃)₂.

Mass of Ca(NO₃)₂ = 100 g

Molar mass of Ca(NO₃)₂ = 40 + 2[14 + (3×16)]

= 40 + 2[14 + 48]

= 40 + 2[62]

= 40 + 124

= 164 g/mol

Mole of Ca(NO₃)₂ =?

Mole = mass /molar mass

Mole of Ca(NO₃)₂ = 100 / 164

Mole of Ca(NO₃)₂ = 0.61 mole

Answer:

Which of the following pairs lists a substance that can neutralize Ca(OH)2 and the salt that would be produced from the reaction?

HCl and CaCl2

HClO and CaHClO

H2O and Ca(OH)3

H3PO4 and Ca(PO3)2

Explanation:

The given substance is Ca(OH)2 which is a base.

To neutralise a base an acid is required.

Among the given options,

HCl and H3PO4 are the acids.

The salts foremd when calcium hydroxide reacts with the respective acids are CaCl2 and Ca3(PO4)2.

But among the given options, only the forst option that is

HCl and CaCl2 shows the correct formulas.

Hence, the answer is first option.

Answer:

HCl and CaCl2

Explanation:

Answer:

(6 mol)·(-393.5 kJ/mol) + (6 mol)·(-285.83 kJ/mol) - (1 mol)·(-1,273.02 kJ/mol) + (6 mol)·(0 kJ/mol)

Explanation:

Question; From the given options, the chemical reaction in the question is presented as follows;

C₆H₁₂O₆(s) + 6O₂(g) → 6CO₂(g) + 6H₂O(l), given that we have;

[tex]\Delta \text H _f^{\circ}[/tex] for C₆H₁₂O₆ = -1,273.02 kJ/mol

[tex]\Delta \text H _f^{\circ}[/tex] for O₂(g) = 0 kJ/mol

[tex]\Delta \text H _f^{\circ}[/tex] for CO₂(g) = -393.5 kJ/mol

[tex]\Delta \text H _f^{\circ}[/tex] for H₂O(l) = -285.83 kJ/mol

The heat or enthalpy of a reaction,  is given as follows;

[tex]\Delta\text H_{rxn}^{\circ} = \sum \text n \cdot \Delta \text H _f^{\circ}(\text {products}) - \sum \text m \cdot \Delta \text H _f^{\circ}(\text {reactants} \text)[/tex]

Therefore, the equation which should be used to calculate [tex]\Delta\text H_{rxn}^{\circ}[/tex], is given as follows;

[tex]\sum \text n \cdot \Delta \text H _f^{\circ}(\text {products})[/tex] = (6 mol)·(-393.5 kJ/mol) + (6 mol)·(-285.83 kJ/mol)

[tex]\sum \text m \cdot \Delta \text H _f^{\circ}(\text {reactants} \text)[/tex] = (1 mol)·(-1,273.02 kJ/mol) + (6 mol)·(0 kJ/mol)

Therefore;

[tex]\Delta\text H_{rxn}^{\circ}[/tex] = (6 mol)·(-393.5 kJ/mol) + (6 mol)·(-285.83 kJ/mol) - (1 mol)·(-1,273.02 kJ/mol) + (6 mol)·(0 kJ/mol)

Too lazy to draw sorry lol.

#CarryOnLearning

I actually just looked it up via image search.

just copy by hand either of the flow charts.

if you can, use colors to fill. makes it more interesting to look at

and define a circle (or rather a few points on it) to draw it neatly. the defined points can later be transformed into the arrows.

i know the answer is a theory

Hi there!

[tex]\large\boxed{3.203 * 10^{22} atoms}[/tex]

We can use the following conversions to solve:

Total mass --> amount of mols --> amount of atoms (Avogadro's number)

Begin by calculating the amount of boron trifluoride in 3.61 grams:

3.61 g * (1 mol BF₃ / 67.8 g) ≈ 0.0532 mol BF₃

Use avogadro's number to convert:

0.0532 mol * 6.02× 10²³atoms / 1 mol = 3.203 × 10²² atoms

Answer:

Explanation:

Why is there a star * behind the question.

CaCl2

Al2(SO4)3

NaOH

Answer:

Answer to the following question is as follows.

Explanation:

Acid rain causes harm to houses and buildings by dissolving stone or corroding metal exposed to the elements. Acid rain can degrade calcium carbonate or calcium-based chemicals found in some of these products.

The acidic particles damage metal and accelerate the deterioration of paint and stone. They also make buildings and other structures, like as monuments, filthy.

Answer:

resend again that question dear

Answer:

3

Explanation:

The reaction for the extraction of Iron is :-

2Fe2O3(s) + 3C(s) → 4Fe(l) + 3CO2(g)

change in oxidation state (O.S.) = higher O.S - lower O.S

= 3 - 0

= 3

Answer:

true

Explanation:

As an atom with no charge have same number of proton and electrons

Answer:

This is a chemical symbol for Potassium Bromide

Elements in the same family have the same number of protons. This  statement is not true about the periodic table. Therefore, option A is correct.

The chemical elements are arranged in rows and columns in the periodic table, sometimes referred to as the periodic table of the elements. It is frequently used in physics, chemistry, and other sciences and is frequently regarded as a symbol of chemistry.

The table can be used by scientists to anticipate chemical reactions, study trends in the periodic properties of certain elements, and speculate on the properties of yet-to-be-discovered elements. The elements are arranged in the contemporary periodic table according to their atomic numbers and periodic characteristics.

The periodic table has changed to represent more than 150 years of chemical and physics research and development.

Thus, option A is correct.

To learn more about the periodic table, follow the link;

https://brainly.com/question/11155928

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Answer:

D Period 1, Group 18

Explanation:

it's helium

it's top right corner of the periodic table

Answer;

P4O10 - molecular solid

Graphite - network solid

Ammonium phosphate - ionic

Brass - metallic

SiC - network solid

Rb- metallic

I2 - molecular

LiBr- ionic

P4 - molecular

Plastic - amorphous

Si - network

Explanation:

An ioinc solid is made up of a pair of oppositely charged ion held together by electrostatic interaction between the bonding species.

A covalent solid is a solid in which the atoms involved in the solid are bonded together by covalent bonds. Covalent solids are also molecular.

Metals are held together by interaction of metal ions and a sea of electrons. This is called the metallic bond.

A network solid is composed of covalently bonded atoms that repeat itself in a definite manner. E.g SiC

Answer:

C.faste-moving lava flows and explosion of cinder

Answer:

65.2%

Explanation:

It is given that :

[tex]$2NO + O_2 \rightarrow 2NO_2$[/tex]

Therefore, 60 g of nitrogen oxide will produce 92 g of nitrogen dioxide

or 60 kg of nitrogen oxide will produce 92 kg of nitrogen dioxide

or 1500 kg of nitrogen oxide will produce [tex]2300\ kg[/tex] of nitrogen dioxide

Therefore the percentage yield = (Actual yield / Expected yield) x 100

percentage yield = [tex]$\frac{1500}{2300} \times 100$[/tex]

Percentage yield = 65.217 %

Answer:

the person above me is correct, the answer for this is 65.2% or option D!

Explanation:

thank you person above me! i got a 100% on the test! :D

Answer:

VSEPR theory

Explanation:

The valence shell electron pair repulsion theory was propounded by Gillespie and Nylom (1957).

The entire idea of the VSEPR theory is that the shape of a molecule depends on the electrostatic repulsion between electron pairs surrounding the central atom in a molecule which causes these pairs to be separated as far as possible.

The shapes of many molecules can be accurately predicted based on this model.

The required temperature of the gas sample is -64.96 °C.

Ideal gas equation gives idea about the behavior of gas at different condition & represented as:

PV = nRT.

From the above equation it is clear that relation between temperature and pressure for this question is:

P₁/T₁ = P₂/T₂, where

P₁ & T₁ are the initial pressure and temperature.

P₂ & T₂ are the final pressure and temperature.

On putting values, we get

T₂ = (145)(-25) / (55.8) = -64.96 °C

Hence required temperature of the sample is -64.96 °C.

To know more about ideal gas equation, visit the below link:
https://brainly.com/question/1056445

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Answer:

See explanation

Explanation:

Calcium carbide reacts with water to yield acetylene gas and calcium hydroxide as follows;

CaC2(s)+2H2O(g)⇋Ca(OH)2(s)+C2H2(g)

This now shows us that the equation as written in the question is wrong. Since the equation for the reaction of calcium carbide and water as shown in the question is wrong, the equation can not be balanced.

Answer

Tq so much.

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Answer:

Thank you so much.

Answer:

This answer I think it is Al,F