How many grams of calcium chloride are required to make 20 grams of calcium hydroxide? CaCl2 + 2 NaOH → Ca(OH)2 + 2 NaCl

Answer:

If a solution has pH=8 , then its pOH is 14−8=6 and the corresponding concentration of hydroxyl OH− ions is 10−6 mol per litre.

Explanation:

Answer:

the half-life of the compound is 223 minutes

Explanation:

Given the data in the question;

compound decomposes by a first-order process,

17% of compound decomposes in 60 minutes,

the half-life of the compound = ?

Since its a first order reaction, we use the expression;

k = 1/t ln( Co/Cf )

given that; t = 30 minutes, Cf = 1 - 17% of Co = 1 - 0.17 of Co = 0.83Co

we substitute

k = ( 1 / 60 min ) ln( Co / 0.83Co )

k =  ( 1 / 60 min ) ln( 1 / 0.83 )

k = 0.016667 × 0.186329578

k = 0.003105555

so get the half life;

[tex]t_{1/2[/tex] = 0.693 / k

we substitute

[tex]t_{1/2[/tex] = 0.693 / 0.003105555

[tex]t_{1/2[/tex] = 223.14 ≈ 223 minutes

Therefore, the half-life of the compound is 223 minutes

Answer:

a. Does not obey Conservation of Mass law

Explanation:

An example of an unbalanced chemical equation is:

As you can see, there are two Na atoms on the right side of the equation, while only one on the left side, causing the masses on both sides of the equation to not be equal. In other words, not fulfilling the Conservation of Mass law.

Compare with the correctly balanced equation:

Now both sides of the equation possess the same number of atoms for each element.

Answer:

The temperature of the sample increase by 48 Kelvin

Explanation:

The sample is identical.

Hence the heat at constant pressure is equal to the heat at the constant Volume

Q1 = Q2

Q 1 = heat at constant pressure

Q2 = heat at the constant Volume

Substituting the given values, we get -

[tex]\frac{3}{2} nRT_1 = \frac{5}{2} nRT_2\\3 * 80 = 5 * T_2\\T_2 = 48[/tex]

The temperature of the sample increase by 48 Kelvin

Answer:

"23.896%" is the right answer.

Explanation:

The given values are:

Mass of NaCl,

= 51.56 g

Mass of H₂O,

= 165.6 g

As we know,

⇒  Mass of solution = [tex]Mass \ of \ (NaCl+H_2O)[/tex]

                                 = [tex]51.56+164.2[/tex]

                                 = [tex]215.76 \ g[/tex]

hence,

⇒ [tex]Mass \ percent =\frac{Mass \ of \ NaCl}{Mass \ of \ solution}\times 100[/tex]

                           [tex]=\frac{51.56}{215.76}\times 100[/tex]

                           [tex]=23.896 \ percent[/tex]

Answer:

The change in entropy is -1083.112 joules per kilogram-Kelvin.

Explanation:

If the water is cooled reversibly with no phase changes, then there is no entropy generation during the entire process. By the Second Law of Thermodynamics, we represent the change of entropy ([tex]s_{2} - s_{1}[/tex]), in joules per gram-Kelvin, by the following model:

[tex]s_{2} - s_{1} = \int\limits^{T_{2}}_{T_{1}} {\frac{dQ}{T} }[/tex]

[tex]s_{2} - s_{1} = m\cdot c_{w} \cdot \int\limits^{T_{2}}_{T_{1}} {\frac{dT}{T} }[/tex]

[tex]s_{2} - s_{1} = m\cdot c_{w} \cdot \ln \frac{T_{2}}{T_{1}}[/tex] (1)

Where:

[tex]m[/tex] - Mass, in kilograms.

[tex]c_{w}[/tex] - Specific heat of water, in joules per kilogram-Kelvin.

[tex]T_{1}[/tex], [tex]T_{2}[/tex] - Initial and final temperatures of water, in Kelvin.

If we know that [tex]m = 1\,kg[/tex], [tex]c_{w} = 4190\,\frac{J}{kg\cdot K}[/tex], [tex]T_{1} = 373.15\,K[/tex] and [tex]T_{2} = 288.15\,K[/tex], then the change in entropy for the entire process is:

[tex]s_{2} - s_{1} = (1\,kg) \cdot \left(4190\,\frac{J}{kg\cdot K} \right)\cdot \ln \frac{288.15\,K}{373.15\,K}[/tex]

[tex]s_{2} - s_{1} = -1083.112\,\frac{J}{kg\cdot K}[/tex]

The change in entropy is -1083.112 joules per kilogram-Kelvin.

Answer:

Explanation:

Change in entropy,

[tex]\delta S = mCp * In[\frac{T2}{T1}][/tex]

The initial temperature,

[tex]T1 = 100^oC\\\\T1 = 100+273\\\\T1 = 373k[/tex]

Final value of temperature,

[tex]T2 = 15^oC\\\\T2 = 15+273\\\\T2 = 288k[/tex]

where,

[tex]m = 1kg\\\\Cp = 4190 J/kg.k[/tex]

Substitute into [tex]\delta S[/tex]

[tex]\delta S = mCp * In[\frac{T2}{T1}]\\\\\delta S = 1 * 4190 * In[\frac{288}{373}]\\\\\delta S = 4190 * In[0.7721]\\\\\delta S = 4190 * [-0.2586]\\\\\delta S = -1083.534 J/k[/tex]

The negative sign exists because the change in entropy will be decreasing due to cooling.

For more information on this visit

https://brainly.com/question/17756498

Answer:

D) 373 mm Hg.

Explanation:

We can solve this problem by keeping in mind Dalton's law of partial pressures, which states that the total pressure of a mixture of gases is equal to the sum of each gas' partial pressures. In other words, for this case:

The answer is option D) 373 mm Hg.

Answer:

9-10 ppm.

0.2-0.4 ppm.

Explanation:

The proton on the aldehyde group will appear at approximately 9-10 ppm whereas the methylene peak on the alcohol is the only peak 0.2-0.4 ppm for either compound. Aldehydes and aromatics are quite distinctive in the Nuclear magnetic resonance (NMR). Aldehydes show up from 9-10 ppm, usually as a small singlet; aromatic protons show up from 6.5-8.5 ppm. NMR spectroscopy is the use of NMR to study the physical, chemical, and biological properties of matter.

percentage yield =(actual yield/theoretical yield) ×100/1

chlorine is the limiting reagent hence would be the major determinant of the product

71[Cl2]=2×58.5[NaCl]

200[Cl2]=x[NaCl]

x=(200×58.5×2)/(71)

x=329.58g(theoretical yield of NaCl)

percentage yield = (240/329.58) ×100

percentage yield= 72.8℅

The answer is that the percentage yield is 72.8 % .

Chemical reactions in the real world do not always go exactly as planned on paper.

In the course of an experiment, many things will contribute to the formation of less product than would be predicted.

Besides spills and other experimental errors, there are often losses due to an incomplete reaction, undesirable side reactions, etc.

Chemists need a measurement that indicates how successful a reaction has been. This measurement is called the percent yield.

Percentage yield =(actual yield/theoretical yield) ×100 %

Chlorine is the limiting reagent hence would be the major determinant of the product

Molecular weight of Cl₂ is 71

Molecular weight of NaCl is 58.5

For 1 mole of Cl₂ 2 moles of NaCl is produced

so it is given that Cl₂ is 200 grams

= 200/71

=2.82 moles.

=5.63 moles of NaCl

=5.63* 58.5 grams

=329.58 g of Nacl

So , 329.58g is theoretical yield of NaCl

percentage yield = (240/329.58) ×100

percentage yield= 72.8℅

Therefore the percentage yield = 72.8%

To know more about percentage yield

https://brainly.com/question/27492865

#SPJ2

Answer:

87.0%

Explanation:

Step 1: Write the balanced reaction

H₂O₂ ⇒ H₂O + 0.5 O₂

Step 2: Calculate the real yield of oxygen, in grams

We have 375 mL (0.375 L) of O₂ at 42 °C (315 K) and 1.52 atm. First, we will calculate the number of moles using the ideal gas equation.

P × V = n × R × T

n = P × V / R × T

n = 1.52 atm × 0.375 L / (0.0821 atm.L/mol.K) × 315 K = 0.0220 mol

The molar mass of oxygen is 32.00 g/mol.

0.0220 mol × 32.00 g/mol = 0.704 g

Step 3: Calculate the theoretical yield of oxygen, in grams

According to the balanced equation, the mass ratio of H₂O₂ to O₂ is 34.01:16.00.

1.72 g H₂O₂ × 16.00 g O₂/34.01 g H₂O₂ = 0.809 g O₂

Step 4: Calculate the percent yield of oxygen

We will use the following expression.

%yield = real yield / theoretical yield × 100%

%yield = 0.704 g / 0.809 g × 100% = 87.0%

Considering the reaction stoichiometry and the ideal gas law, the percent yield when 1.72 g of H₂O₂ decomposes and produces 375 mL of O₂ gas measured at 42 °C and 1.52 atm is 86.96%.

The balanced reaction is:

2 H₂O₂ → 2 H₂O +  O₂

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:

The molar mass, this is the amount of mass a substance contains in one mole, of H₂O₂ is 34 [tex]\frac{g}{mole}[/tex]. Then, the amount of moles of H₂O₂ that decomposes when 1.72 grams of H₂O₂ reacts is calculated as:

[tex]1.72 gramsx\frac{1 mole}{34 grams}= 0.0506 moles[/tex]

Then you can apply the following rule of three: if by stoichiometry 2 moles of H₂O₂ produce 1 moles of O₂, 0.0506 moles of H₂O₂ will produce how many moles of O₂?

[tex]amount of moles of O_{2} =\frac{0.0506 moles of H_{2} O_{2} x1 mole of O_{2} }{2 moles of H_{2} O_{2}}[/tex]

amount of moles of O₂= 0.0253 moles

On the other side, an ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:

P× V = n× R× T

In this case, for O₂ gas you know:

Replacing:

1.52 atm× 0.375 L = n× 0.082 [tex]\frac{atmL}{molK}[/tex]× 315 K

Solving:

[tex]n=\frac{1.52 atmx 0.375 L}{0.082\frac{atmL}{molK}x 315 K }[/tex]

n= 0.022 moles

The percent yield is calculated as

[tex]Percent yield= \frac{real yield}{theoretical yield} x100[/tex]

In this case, for oxygen the percent yield is calculated as

[tex]Percent yield of oxygen= \frac{0.022 moles}{0.0253 moles} x100[/tex]

Percent yield of oxygen= 86.96 %

Finally, the percent yield when 1.72 g of H₂O₂ decomposes and produces 375 mL of O₂ gas measured at 42 °C and 1.52 atm is 86.96%.

Learn more about:

Answer:

There won't be any equilibrium.

Explanation:

Because when we add a product to a system then the equilibrium will not be the same since the weight will be more on one system which will make it unstable.

Answer:

58.8 grams.

Explanation:

First we calculate how many HNO₃ grams are there in 400.0 g of a 10.0% solution:

Then we calculate the mass of a 68.0% solution that would contain 40 grams of HNO₃:

Answer:

22900 L

Explanation:

Assuming the gas behaves ideally, we can solve this problem by using Boyle's law, which states that:

Where subscript 1 refers to the initial conditions of pressure and volume (within the bomb, namely), while 2 refers to the final conditions.

Meaning that in this case:

We input the data:

And solve for V₂:

Answer:

it has volume( takes up space).

Explanation:

The characteristics of matter are that it has mass and also exhibits volume (takes up space).Hence Option (C) is Correct.

A physical substance in general, that which occupies space and possesses rest mass, especially as distinct from energy.

Matter is important because it makes up everything around us and matter can not be created or destroyed but instead, they just transformed into a different form.

Any characteristic that can be measured, such as an object's density, colour, mass, volume, length, malleability, melting point, hardness, odour, temperature, and more, are considered properties of matter.

Therefore, The characteristics of matter are that it has mass and also exhibits volume (takes up space).Hence Option (C) is Correct.

Learn more about Matter here ;https://brainly.com/question/25860850

#SPJ2

Answer:

more dense

Explanation:

cold air particles are moving slower, because they have less energy.

Answer:

It is bad

Explanation:

Is nuclear energy good or bad?

Which best compares kinetic energy and temperature?

[tex]{\boxed{\mathcal{\red{Answer:}}}}[/tex]

A. Kinetic energy is energy of motion, while temperature is a measure of that energy in substances. ✅

[tex]\circ \: \: { \underline{ \boxed{ \sf{ \color{green}{Happy\:learning.}}}}}∘[/tex]

Answer:

A. Kinetic energy is energy of motion, while temperature is a measure of that energy in substances.

Explanation:

got it right on edge 2021

Answer:

A. Alternating single and double bonds

Explanation:

Hydrocarbons i.e. hydrogen and carbon containing compounds, are grouped into two namely: aliphatic and aromatic hydrocarbons. Aliphatic hydrocarbons contains straight or branched chains of carbon and hydrogen atoms in their structure e.g. alkanes, alkenes etc.

On the other hand, aromatic hydrocarbons are cyclic hydrocarbons containing one or more cyclic rings. The benzene ring is the basis of all aromatic hydrocarbons and one characteristics of benzene is that it possesses an alternating single (-) and double bonds (=) in their structure.

Since benzene is a building constituent of aromatic hydrocarbons, an "alternating single and double bond" is a characteristics of aromatic hydrocarbons.

Answer:

3584.21 J/kg.K

Explanation:

Applying

Q = cm(t₂-t₁)........... equation 1

Where Q = Quantity of heat absorb, c = specific heat capacity of the metal, m = mass of the metal, t₁ = intial temperature, t₂ = Final temperature.

make c the subject of the equation

c = Q/(m(t₂-t₁)........... Equation 2

From the question,

Given: Q = 1362 J, m = 15.2 g = 0.0152 kg, t₁ = 17°C, t₂ = 42°C

Substitute these values into equation 2

c = 1362/0.0152(42-17)

c = 1362/0.38

c = 3584.21 J/kg.K

Answer:

Saturated organic compound has only single bonds between carbon atoms. An important class of saturated compounds are the alkanes. Many saturated compounds have functional groups, e.g., alcohols.

Unsaturated organic compound have double or triple covalent bonds between adjacent carbon atoms. The term "unsaturated" means more hydrogen atoms may be added to the hydrocarbon to make it saturated (i.e. consisting all single bonds).

Answer:

[H+] = 10^-2

Explanation:

pH = -log[H+]

2 = -log[H+]

[H+] = 10^-2

Answer: Temperature and number of moles are the conditions which remain constant in Boyle's law.

Explanation:

Boyle's law states that at constant temperature the pressure of a gas is inversely proportional to the volume of gas.

Mathematically, it is represented as follows.

[tex]P \propto \frac{1}{V}[/tex]

As equation for ideal gas is as follows.

PV = nRT

And, at constant temperature the pressure is inversely proportional to volume which also means that number of moles are also constant in Boyle's law.

Thus, we can conclude that temperature and number of moles are the conditions which remain constant in Boyle's law.

Answer:

Temperature and number of moles

Explanation:

Answer:

349.503 g

https://www.convertunits.com/from/moles+Copper/to/grams

here is a link, you can convert moles of copper to grams here

The answer is 5.50 moles of Cu (Copper) has 349.503 grams mass .

A mole is defined as 6.02214076 × 10²³ atoms, molecules, ions, or other chemical units.

and the molar mass of a substance is defined as the mass of 1 mole of that substance, expressed in grams per mole.

It is equal to the mass of 6.022 × 10 23 atoms, molecules, or formula units of that substance.

1 mole of Cu has 63.546 grams of Cu

So 5.50 moles will have 5.50 * 63.546 grams

=349.503 grams

Therefore 5.50 moles of Cu (Copper) has 349.503 grams mass .

To know more about moles

https://brainly.in/question/148570

#SPJ2

Answer:

0.25 M

Explanation:

First we convert 85.5 grams of sucrose into moles, using its molar mass:

Then we divide the number of moles by the number of liters to calculate the molarity:

Answer:

A

Explanation:

The water potential depends upon the pressure and amount of solute according to the water potential formula.

The following points can be considered:

Therefore, the correct answer is a) pressure and the amount of solute.

Learn more about water potential:

https://brainly.com/question/22177218

Answer:

Acids taste sour while bases taste bitter. An acid reacts with metals to produce bubbles of hydrogen gas while a base feels slimy to the touch. Acids turn blue litmus paper red while bases turn red litmus paper blue.

Answer:

  A. Energy is released

Explanation:

Energy is only released when chemical bonds are formed.