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pH of the Sr(OH)₂ solution : 12.6

pH is the degree of acidity of a solution that depends on the concentration of H⁺ ions. The greater the value the more acidic the solution and the smaller the pH.  

pH = - log [H⁺]  

Sr (OH) ₂ solution is a base with valence 2, so we determine the pOH from the OH ion concentration - which is expressed by pOH = - log [OH -]. After that we determine the pH value from the relationship:

[H⁺] [OH⁻] = Kw=10⁻¹⁴

pH + pOH = 14

Sr(OH)₂⇒Sr²⁺+2OH⁻

From equation [Sr(OH)₂] : [OH⁻]=1 : 2, so [OH⁻]=

[tex]\tt [OH^-]=2\times 2.10^{-2}=4.10^{-2}~M[/tex]

[tex]\tt pOH=-log[OH^-]\\\\pOH=-log~4.10^{-2}\\\\pOH=2-log~4\rightarrow 1.398 \\\\pH+pOH=14\\\\pH=14-1.398\\\\pH=12.6[/tex]

pH is the measurement of the concentration of hydrogen or hydronium ion in an aqueous solution. The pH of strontium hydroxide is 12.6.

The pH is the potential of hydrogen or the negative log of its concentration.

First, calculate the pOH of strontium hydroxide by:

[tex]\begin{aligned} \rm pOH &= \rm - log [OH ^{-}]\\\\&= \rm -log [4\times10^{-2}]\\\\&= 1.398\end{aligned}[/tex]

Now, calculate pH from pOH as:

[tex]\begin{aligned}\rm pH &= 14 - \rm pOH\\\\&= 14 - 1.398\\\\&= 12.6\end{aligned}[/tex]

Therefore, 12.6 is the pH of strontium hydroxide.

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Answer:

4.63 mol

Explanation:

Step 1: Write the balanced complete combustion reaction of acetylene

2 C₂H₂(g) + 5 O₂(g) ⟶ 4 CO₂(g) + 2 H₂O(g)

Step 2: Establish the appropriate molar ratio

According to the balanced equation, the molar ratio of C₂H₂ to O₂ is 2:5.

Step 3: Calculate the number of moles of O₂ needed to react with 1.85 moles of C₂H₂

We will use the stoichiometric molar ratio.

1.85 mol C₂H₂ × (5 mol O₂/2 mol C₂H₂) = 4.63 mol O₂

Answer:

Yes

Explanation:

Text me on here

Answer:

Over time, the plant matter transforms from moist, low-carbon peat, to coal, All types of coal also contain sulfur, which, when burned, releases toxic air pollution. Sulfur All this coal comes from mines, which are either underground or run on diesel—a major source of air toxins, nitrogen oxide, and soot.

Answer:

38.3 miles

Explanation:

First, we convert 1.95 gallons to mililiters:

Then we calculate how many grams of octane are available for the reaction, using its density:

Now we convert octane grams into octane moles, using its molar mass:

Then we calculate how many kJ are produced from the combustion of  44.78 mol C₈H₁₈, if 2 moles produce 10900 kJ:

We calculate how many seconds is the car available to keep going, if it spends 115 kJ per second:

We convert seconds to hours:

Finally we calculate the distance:

Answer:

FeCl3 + 3KOH → Fe(OH)3 + 3KCl

Explanation:

Answer:

Atoms of the same element have the same chemical properties. The only differences between atoms of the same element are the number of neutrons in the nucleus and the atomic weight of each isotope. false

Answer:

False

Explanation:

Different elements can have different properties, but not atoms of the same element

Answer:

Explanation:

The lewis structure (indicating all the atoms and patterns provided as hint in the question) of glycine can be seen in the attachment below. While the chemical structure of glycine can be seen below

         H

          |

H₂N - C - C =O

          |      \

         H      OH

The structure (of glycine) above provides a "fair idea" of how the lewis structure will be.

There are 12 atoms of Oxygen, since 3 times 4 is 12.

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Answer:

40

Explanation:

it is push i think to move the car

Answer:

Either A. Push or B.Pull because the truck is either pushing or pulling the car to move it. So it depends on if it's pushing or pulling the car.

Explanation:

Answer: 2

Explanation:

A combustion reaction must include O2 as a reactant.

An inorganic substance almost never includes carbon.

So, by process of elimination:

1. Carbon is a reactant = probably not

2. Has O2, no carbon = yes

3. O2 is not a reactant = no

4. Carbon is a reactant = probably not

An example of the combustion of an inorganic substance is:

2 Ca + O₂ ⇒ 2 CaO

We have 4 reactions and we want to determine which is an example of combustion of an inorganic substance.

A combustion reaction is a reaction in which a substance reacts with oxygen gas, releasing energy in the form of light and heat.

Organic substances always contain carbon while most inorganic substances do not contain carbon.

Let's consider the following reactions.

This is a combustion reaction but C₃H₈ is an organic substance.

This is an example of the combustion of an inorganic substance.

This is not a combustion reaction.

This is a combustion reaction but CH₃COOH is an organic substance.

An example of the combustion of an inorganic substance is:

2 Ca + O₂ ⇒ 2 CaO

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Answer: A. Kinetic energy increases during exothermic changes and decreases during endothermic changes

Explanation: During an exothermic change potential energy is converted to kinetic energy. I hope this is correct. :)

Answer:

C

Explanation:

Answer:

V₁ = 0.585 L

Explanation:

Given data:

Initial pressure = 151 mmHg

Initial volume = ?

Final pressure = 166 mmHg

Final volume = 0.532 L

Solution:

The given problem will be solved through the Boyle's law,

"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"

Mathematical expression:

P₁V₁ = P₂V₂

P₁ = Initial pressure

V₁ = initial volume

P₂ = final pressure

V₂ = final volume  

Now we will put the values in formula,

P₁V₁ = P₂V₂

151 mmHg × V₁ = 166 mmHg × 0.532 L

V₁ = 166 mmHg × 0.532 L / 151 mmHg

V₁ = 88.312mmHg .L /151 mmHg

V₁ = 0.585 L

Answer:

Decomposition reaction.

There's heating of solid Ammonium nitrate to form di nitrogen oxide and water

Answer:

A

Explanation:

A is the correct answer once the warm, moist air moves into the cold, dry air, the thunderstorm will start to develop and gradually get larger.

Answer:

1 - concentrated solution

2- dilute solution

3- solubility

4- saturated solution

5- supersaturated solution

6- unsaturated solution

7- acid

8- base

9- corrosive

10- indicator

Explanation:

Answer:

See explanation

Explanation:

The equation of the reaction is;

C 2 H 6 O(l)  +  3 O 2 (g)  → 2 CO 2 ( g )  +  3 H 2 O(l )

Next we have to determine the limiting reactant, this reactant gives the least number of moles of product.

Number of moles of C 2 H 6 O = mass/molar mass = 1.86g/ 46.07 g/mol = 0.04 mols

From the equation;

1 mol of ethanol yields 2 mols of CO2

0.04 moles of ethanol yields 0.04 * 2/1 = 0.08 mols of CO2

For water;

1 mol of ethanol yields 3 mols of water

0.04 moles of ethanol yields 3 * 0.04/1 = 0.12 mols of water

Also;

Number of moles of oxygen= 10g/32g/mol = 0.31 moles

3mols of O2 yields 2 moles of CO2

0.31 moles of O2 yields 0.31 * 2/3 = 0.21 moles of CO2

For water;

3 moles of O2 yields 3 moles of water

0.31 moles of O2 yields 0.31 * 3/3 = 0.31 moles of water

Hence ethanol is the limiting reactant.

From  PV=nRT

Volume of CO2 is;

V = nRT/P

V = 0.08 * 0.082 *298/1 = 1.95 L

Volume of water;

V = nRT/P

V= 0.12 * 0.082 * 298/1

V= 2.93 L

Total volume of gases after reaction = 1.95 L + 2.93 L = 4.88 L

Answer:

795k

Explanation:

C÷5=k-273÷9

290÷5 = k - 273 ÷ 9

k = 795

The relative humidity on a starry summer night is determined as 91%.

The dry bulb depression temperature is calculated as follows;

ΔT = 19⁰C - 18⁰C   =  1⁰C

at dry bulb temperature of 18⁰C and depression temperature of 1⁰C, the relative humidity is determined as 91%.

Thus, the relative humidity on a starry summer night is determined as 91%.

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Answer:

BIPHASIC LIQUIDS are used ear cleaning, to softening the wax so that mild infections can be treated.

Explanation:

BIPHASIC LIQUIDS are liquids that contain two immiscible phases, one is suspension and the other is emulsion. In suspension, the finely solid are dispersed in a liquid or semi solidwhich is use for medicament

The emulsion consist of immiscible liquids, one is dispersed in globules.

They are used ear cleaning, to softening the wax so that mild infections can be treated.

Given

the structure of the alkanes

Required

match the image to the name

Solution

Alkanes are saturated hydrocarbons with all of the carbon bonds being single bonds

General formula:

[tex]\large {\boxed {\bold {C_nH_2n + 2}}}[/tex]

If we look at the picture, we define the black atom as Carbon and the branch is Hydrogen

To determine the name of the alkane, all we have to do is count the number of Carbon atoms

Butane : C₄H₁₀ : 4 C atoms

Methane : CH₄ : 1 C atom

Ethane : C₂H₆ : 2 C atoms

Propane : C₃H₈ : 3 C atoms

Answer:

Solid

Explanation:

In solid there are strong intermolecular forces present as compared to liquid and gas. This is why solid are in more packed form as compared to liquid and gas. In liquid and gas intermolecular forces are week that's why molecules are away from each other and occupy more space.

Properties of gases:

Molecule of gases randomly move everywhere and occupy all available space.

Gases don't have definite volume and shape and take the shape and volume of container in which it present.

Their densities are very low as compared to the liquid and solids.

Gas molecules are at long distance from each other therefore by applying pressure gases can be compressed.

The very weak inter molecular forces are present between gas molecules.

Properties of Liquid:

Liquid have definite volume but don't have definite shape.

Their densities are high as compared to the gases but low as compared to the solids.

In liquid, molecules are close to each other and have greater inter molecular forces as compared to the gas molecules.

Properties of solids:

Solids have definite volume and shape.

In solids molecules are tightly pack and very close to each other.

Their melting and boiling point are every high.

The densities of solids are also very high as compared to the liquid and gas.

There are very strong inter molecular forces are present between solid molecules.

Answer:

A: Solid

Explanation:

Correct with Acellus

Answer:

Number of moles = 1.57 mol

Explanation:

Given data:

Mass of propanol = 94.1 g

Molar mass of propanol = 60.1 g/mol

Number of moles of propanol = ?

Solution:

Formula:

Number of moles = mass/molar mass

by putting values,

Number of moles = 94.1 g/ 60.1 g/mol

Number of moles = 1.57 mol

Answer: I think it is D

Explanation:

Answer:pull

Explanation:

The sentences that probably comes from a work of classic literature are:

The great literary works of Greek, Roman, and other prehistoric civilizations are referred to as classical literature. Classical literature includes the writings of Homer, Ovid, and Sophocles. The phrase isn't just applicable to books. It can also incorporate other types of writing, such as epic, lyric, tragedy, comedy, and pastoral.

Classical literature enables us to take a profound plunge into the lives, worldviews, and mindsets of individuals we have never met, to travel to unfamiliar settings, and to comprehend eras we will never be able to experience ourselves.

Therefore, option C and D are correct.

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Answer:

Mendeleev's greatest contribution to science is certainly the Periodic Table of Elements, which says the properties of basic elements repeat periodically when they are arranged by their atomic number. He made the discovery in 1869 during his work on the award-winning textbook on chemistry basics.

Inventions: Periodic table, Pyrocollodion

Explanation:

*Hope this helps*

Answer:

Mendeleev's greatest contribution to science is certainly the Periodic Table of Elements, which says the properties of basic elements repeat periodically when they are arranged by their atomic number. He made the discovery in 1869 during his work on the award-winning textbook on chemistry basics.

Inventions: Periodic table, Pyrocollodion

Explanation:

Answer:

the answer is b

Explanation:

brcause the gravutational pull on the moon is lower than on earth...