The enthalpy of sublimation of iodine is 60.2 kJ/mol, and its enthalpy of vaporization is 45.5 lz.1/mol. What is the enthalpy of fusion of iodine?

Answer:

All substances that are  made up of the same kind of mole ules are called pure substances.

So what do you mean ?

Explanation:

Answer: all matter is made up of pure substance

Explanation:

Answer:

B. PhCHO

Explanation:

Every organic group shows a characteristic IR absorption at certain wavelength . With the help of these absorption spectra we can identify the group present on organic molecules .

The wave number of 2710 cm⁻¹ is absorbed by aldehyde bond stretching .

The wave number of 1705 cm⁻¹ is shown by conjugated aldehyde . So the most likely compound among given compounds is PhCHO .

Answer:

[tex]\% m/m=10.1\%[/tex]

Explanation:

Hello,

In this case given the molal solution of sucrose, we can assume there are 0.329 moles of sucrose in 1 kg of solvent, thus, computing both the mass of sucrose and solvent in grams, we obtain:

[tex]m_{sucrose}=0.329mol*\frac{342g}{1mol}=112.5g[/tex]

[tex]m_{solvent}=1000g[/tex]

In such a way, we proceed to the calculation of the mass percent as follows:

[tex]\% m/m=\frac{112.5g}{112.5g+1000g}*100\%\\ \\\% m/m=10.1\%[/tex]

Regards.

Answer:

a) 2KOH + NiSO₄ → K₂SO₄ + Ni(OH)₂

b) Ni(OH)₂

c) KOH

d) 0.927 g

e) K⁺=0.067 M, SO₄²⁻=0.1 M, Ni²⁺=0.067 M

Explanation:

a) The equation is:

2KOH + NiSO₄ → K₂SO₄ + Ni(OH)₂   (1)        

b) The precipitate formed is Ni(OH)₂  

c) The limiting reactant is:

[tex] n_{KOH} = V*M = 100.0 \cdot 10^{-3} L*0.200 mol/L = 0.020 moles [/tex]

[tex] n_{NiSO_{4}} = V*M = 200.0 \cdot 10^{-3} L*0.150 mol/L = 0.030 moles [/tex]

From equation (1) we have that 2 moles of KOH react with 1 mol of NiSO₄, so the number of moles of KOH is:

[tex] n = \frac{2}{1}*0.030 moles = 0.060 moles [/tex]                  

Hence, the limiting reactant is KOH.  

d) The mass of the precipitate formed is:

[tex] n_{Ni(OH)_{2}} = \frac{1}{2}*n_{KOH} = \frac{1}{2}*0.020 moles = 0.010 moles [/tex]

[tex] m = n*M = 0.010 moles*92.72 g/mol = 0.927 g [/tex]  

e) The concentration of the SO₄²⁻, K⁺, and Ni²⁺ ions are:

[tex]C_{K^{+}} = \frac{2*\frac{1}{2}*n_{KOH}}{V} = \frac{0.020 moles}{0.300 L} = 0.067 M[/tex]  

[tex]C_{SO_{4}^{2-}} = \frac{\frac{1}{2}*n_{KOH + (0.03 - 0.01)}}{V} = \frac{0.030 moles}{0.300 L} = 0.1 M[/tex]

[tex]C_{Ni^{2+}} = \frac{0.020 moles}{0.300 L} = 0.067 M[/tex]

I hope it helps you!                                                                        

The mass of precipitate formed is 0.93 g .

The equation of the reaction is;

NiSO4(aq) + 2KOH(aq) ---->K2SO4(aq) + Ni(OH)2(s)

The precipitate that forms is Ni(OH)2(s).

To obtain the limiting reactant;

Number of moles of NiSO4 = 200/1000 × 0.150 M = 0.03 moles

Number of moles of KOH = 100/1000 × 0.200 M = 0.02 moles

Since 1 mole of NiSO4 reacts with 2 moles of KOH

x moles of NiSO4 reacts with 0.02 moles of KOH

x =  1 mole  ×  0.02 moles/2 moles  = 0.01 moles of NiSO4

Hence, KOH is the limiting reactant.

Now;

Since 2 mole of KOH yields 1 mole of Ni(OH)2

0.02 moles of KOH yields 0.02 moles ×  1 mole/ 2 mole  = 0.01 moles of  Ni(OH)2

Mass of  Ni(OH)2 produced =  0.01 moles of  Ni(OH)2 × 93 g/mol = 0.93 g

Learn more: https://brainly.com/question/9743981

Answer:

Ferrous hydroxide or iron (II) hydroxide.

Explanation:

Hello,

In this case, for the nomenclature of hydroxides we can use two styles:

a. IUPAC: it points out the oxidation state of the given metal by using suffixes ous or ic for metals having to oxidation states, thus, since +2 for iron is the first one, it turns out ferrous hydroxide.

b. Stock: it points out the oxidation state of the given metal by writing it inside parenthesis, thus, it turns out iron (II) hydroxide.

Regards.

The full name of the compound is ferrous hydroxide or iron (II) hydroxide.

Ionic compounds are formed when ions with opposing negative and positive charges form ionic bonds and form compounds, which are compounds made of ions.

Ionic compounds are named by stating the cation first, followed by the anion. When a neutral atom loses one or more electrons, it acquires a positive charge and is called a cation and when an atom gains one or more electrons, it becomes an anion and acquires a negative charge.

Learn more about Naming of compounds, here:

https://brainly.com/question/30962696

#SPJ6

Answer:

See explanation

Explanation:

Homemade pH test strips make it a bit difficult to identity the colours that indicate various values of pH on a pH colour scale. These homemade pH strips make the results of the experiment more prone to human error. Also the creator of the test strip is also prone to human error during the creation of the strip.

The commercial pH test strips are more accurate when used.

Answer:

22.0 g

Explanation:

To find the mass, multiply the volume by the density.

8 cm³  ×  2.75 g/cm³  =  22.0 g

The marble is 22.0 g.

The correct answer is B. All liquids are denser than the ball, and honey is denser than corn syrup and maple syrup.

Explanation:

Differences in density cause substances such as solids or liquids to float or sink. In general, the substance sinks if it is denser, or floats if it is less dense. In this context, honey is the substance with the most density because it is at the bottom of the container. Also, honey is followed in density by maple syrup, and then by corn syrup. Moreover, if the ping pong ball floats in the most superficial layer, it is because this is less dense than any of the liquids. According to this, it can be concluded honey is denser than the other liquids, and the liquids are denser than the ball (option B.)

Answer:

b is right  ( all liquids are denser than the ball and honey is denser than corn syrup.)

Explanation:

Answer: pH = 4.3

Explanation: The pH of a buffer solution and its conjugate base can be determine by the Henderson-Hasselbach Equation. It can be estimated because equilibrium between weak acid and its conjugate base allows the solution to not change pH when small amounts of strong acid or base are added.

pH is calculated by:

[tex]pH = pK_{a} + log(\frac{[conjugate]}{[acid]} )[/tex]

pKa is the acidic dissociation constant and it shows how much strong an acid can be. It is determined as:

[tex]pK_{a}=-log(K_{a})[/tex]

For the buffer solution:

[tex]pK_{a}=-log(8.3.10^{-5})[/tex]

[tex]pK_{a}=4.081[/tex]

Calculating pH:

[tex]pH = 4.081 + log(\frac{0.480}{0.260} )[/tex]

[tex]pH = 4.081 + log(1.846)[/tex]

pH = 4.3

For this buffer solution and its conjugate, pH = 4.3

Answer:

By designing new technology that would prove new information

Explanation:

im not sure about the answer but i just did the test and "by designing new technology that would prove the new information was wrong" isint the answer

Answer:

c. CH3CH2CH2CH3 > d. CH3CH(CH3)2 > b. CH3CH2CH3 > a. CH3CH3

Explanation:

Hello,

In this case, considering the physical properties of hydrocarbons we find that the longer the carbon chain, the higher the boiling point as more energy is required for the phase transition from liquid to gas, thus, we see that c. CH3CH2CH2CH3 and d. CH3CH(CH3)2 have the highest boiling points since they have four carbons both. Then, we have b. CH3CH2CH3 which has three carbon atoms and the lowest boiling point is had by a. CH3CH3.

Nevertheless for both c. and d. we can see that c. has a straight chain whereas d. a branched chain, it means that c, has the highest boiling point due to the higher surface area for energy transfer.

Therefore, the order from highest to lowest is:

c. CH3CH2CH2CH3 > d. CH3CH(CH3)2 > b. CH3CH2CH3 > a. CH3CH3

Regards.

Answer:

Explanation:

In 150 ml of .06 g / ml solution , gram of iodine = 150 x .06 g = 9 g

Let volume of given concentration of .12 g / ml required be V

In volume V , gram of iodine = V x .12 g

According to question

V x .12 = 9 g

V = 9 / .12 = 75 ml

So, 75 ml of .12 g/ml will be taken and it is diluted to the volume of 150 ml to get the solution of required concentration .

Answer:

There are [tex]5.408\times 10^{22}[/tex] grams contained in all the seawater in the world.

Explanation:

At first let is determinate the total mass of seawater ([tex]m_{sw}[/tex]), measured in grams, in the world by definition of density and considering that mass is distributed uniformly:

[tex]m_{sw} = \rho_{sw}\cdot V_{sw}[/tex]

Where:

[tex]\rho_{sw}[/tex] - Density of seawater, measured in grams per liters.

[tex]V_{sw}[/tex] - Volume of seawater, measured in liters.

If [tex]V_{sw} = 1.5\times 10^{21}\,L[/tex] and [tex]\rho_{sw} = 1030\,\frac{g}{L}[/tex], then:

[tex]m_{sw}=\left(1030\,\frac{g}{L} \right)\cdot (1.5\times 10^{21}\,L)[/tex]

[tex]m_{sw} = 1.545\times 10^{24}\,g[/tex]

The total mass of sodium chloride is determined by the following ratio:

[tex]r = \frac{m_{NaCl}}{m_{sw}}[/tex]

[tex]m_{NaCl} = r\cdot m_{sw}[/tex]

Given that [tex]m_{sw} = 1.545\times 10^{24}\,g[/tex] and [tex]r = 0.035[/tex], the total mass of sodium chloride in all the seawater in the world is:

[tex]m_{NaCl} = 0.035\cdot (1.545\times 10^{24}\,g)[/tex]

[tex]m_{NaCl} = 5.408\times 10^{22}\,g[/tex]

There are [tex]5.408\times 10^{22}[/tex] grams contained in all the seawater in the world.

Following are the calculation to the total mass of sodium chloride in grams:

Given:

Seawater volume[tex]= 1.5 \times 10^{21}\ L\\\\[/tex]

Seawater density [tex]= 1.03\ \frac{g}{mL}\\\\[/tex]

[tex]\%[/tex] of sodium chloride in seawater [tex]= 3.5\ \%[/tex]

To find:

The total mass of sodium chloride in grams=?

Solution:

The total volume of seawater [tex]= 1.5 \times 10^{21}\ L= 1.5 \times 10^{24}\ mL\\\\[/tex]

The density of seawater [tex]= 1.03 \frac{g}{mL}[/tex]

[tex]\therefore\\\\[/tex]

Seawater mass = Seawater volume [tex]\times[/tex] density

                           [tex]= 1.5 \times 10^{24}\times 1.03 \ g\\\\= 1.545 \times 10^{24}\ g\\\\[/tex]

[tex]\%[/tex] of sodium chloride in seawater [tex]= 3.5\ \%[/tex]

[tex]\therefore\\\\[/tex]

Calculating the sodium chloride mass in Seawater:

[tex]= 3.5\% \ \ of\ \ 1.545 \times 10^{24} \ g\\\\ =\frac{3.5}{100} \times 1.545 \times 10^{24}\ g\\\\= 5.4075 \times 10^{22} \ g\\\\[/tex]

Calculating the sodium chloride mass [tex]= 5.4075 \times 10^{22} \ g\\\\[/tex]

Learn more:

brainly.com/question/2809961

Answer:

Transcription

Explanation:

Transcription is when you make a copy of the RNA from DNA. This is how the mRNA can leave the nucleus which exists to the cytoplasm and into ribosomes where protein synthesis occurs.

Answer:

BHx, x=3

CHx, x=4

NHx, x=3

CH2Clx, x=2

Explanation:

We have to know that the value of x must depend on the valency of the central atom. If we look at each of the species;

Boron has a common valency of 3

Carbon has a common valency of 4

Nitrogen has a common valency of 3

The valency of each elements will determine the most likely value of x as outlined in the answer above.

Answer:

A. Lacto-N-fucopentaose binds to surface receptors on pathogenic bacteria and prevents them from entering epithelial cells in the intestine.

C. Lacto-N-tetraose is a food source for bacteria that aid in digestion of this and other oligosaccharides.

Explanation:

Human milk contains high levels of indigestible Human milk oligosaccharides (HMOs). It is believed that these HMOs influence the process of coevolution of the nursing infant and its microbiome. Lacto-N-fucopentaose (LNFP) is a carbohydrate (i.e., an oligosaccharide) found in human milk. This oligosaccharide is a bioactive molecule that acts as a substrate for the development of the intestinal microflora. LNFP binds to proteins (to form glycoproteins) and lipids (to form glycolipids) localized on the surface of cells. Moreover, Lacto-N-tetraose (LNT) is also an oligosaccharide found in human milk, which is used as food supplement. It has been shown that LNT prevents infection by inhibiting the adhesion mechanism of harmful bacteria and their toxins. Furthermore, LNT stimulates the development of the microbiome in early life.

Answer:

False

False

they both will stay on the water

Hope this helped

Answer:

c because a chemical process is when something changes into another thing which the wood would be doing if you burned it

Answer:

[tex]CrO_3[/tex]

Explanation:

Hello,

In this case, considering that the compound is 48% oxygen, we infer it is 52% chromium, therefore, by using their atomic masses we compute the moles by assuming those percentages as masses:

[tex]n_{Cr}=52g*\frac{1mol}{52g}=1mol\\ \\n_O=48g*\frac{1mol}{16g}=3mol[/tex]

Next, by dividing by the smallest moles, we find the subscripts in the empirical formula:

[tex]Cr=\frac{1}{1} =1\\\\O=\frac{3}{1} =3[/tex]

Which are also expressed in the smallest whole numbers, therefore the empirical formula is:

[tex]CrO_3[/tex]

Which corresponds to the chromic oxide or chromium (IV) oxide.

Regards.

"The bird bobbed its head up and down" it is qualitative. So, A is correct.

Quantitative data is numbers-based, countable, or measurable. Qualitative data is interpretation-based, descriptive, and relating to language. Quantitative data tells us how many, how much, or how often in calculations. Qualitative data can help us to understand why, how, or what happened behind certain behaviors.

That statement given in the question is not telling us about any quantity or any number, it is telling us about certain behavior.

Quantitative Information – Involves a measurable quantity—numbers are used. Some examples are length, mass, temperature, and time. Quantitative information is often called data, but can also be things other than numbers. Qualitative Information – Involves a descriptive judgment using concept words instead of numbers.

Therefore, "The bird bobbed its head up and down" it is qualitative. So, A is correct.

Learn more about quantitative and qualitative, here:

https://brainly.com/question/12831013

#SPJ7

Answer:

13.64.

Explanation:

Hello,

In this case, since the the specific gravity is computed as the ratio of the density of the given substance by the density of water that is approximately 0.997 g/mL as shown below:

[tex]s.g=\frac{\rho}{\rho _{water}}[/tex]

In such a way, for this case, we find:

[tex]s.g=\frac{13.6g/mL}{0.997g/mL}=13.64[/tex]

Which is dimensionless due the g/mL simplification.

Best regards.

The specific gravity of mercury is 13.61

Specific gravity is defined as the ratio of the density of a substance to the density of water. Mathematically;

[tex]sg=\frac{\rho_s}{\rho_{water}}[/tex]

Given the following parameters:

[tex]\rho_{Hg}=13.6g/mL\\\rho_{H_2O}=0.9998g/mL[/tex]

Substitute the given parameters into the formula;

[tex]sg=\frac{13.6g/mL}{0.9998g/mL}\\sg=13.61[/tex]

Hence the specific gravity of mercury is 13.61

Learn more on specific gravity here: https://brainly.com/question/25782570

Answer:

Octagon > Hexagon > pentagon > square and rectangle > triangle

Explanation:

As we know that

Triangle contains 3 slides

Rectangle contains 4 slides

Square contains 4 slides

Octagon contains 8 slides

hexagon contains 6 slides

Pentagon contains 5 slides

Now based on this

The ranking is as follows

Octagon > Hexagon > pentagon > square and rectangle > triangle

This is the correct order from high to low

Answer:

Explanation:

2 NH₄ClO₄ ⇒ N₂ + Cl₂ + 2O₂ + 4 H₂O

2 moles          1 mole

We are required to produce 1.4 moles of N₂ from ammonium perchlorate .  

1 mole of N₂ is produced by 2 moles of ammonium perchlorate

1.4 moles of N₂ will be produced by 2 x 1.4 = 2.8 moles of ammonium perchlorate .

Answer is 2.8 moles .

The change in the density of a material, if you have a larger piece of it, is the density will remain the same because mass and volume will remain the same. The correct option is C.

Density is mass per volume. It is calculated by dividing the mass by the volume of the substance. It is a scalar quantity, and it is denoted by rho a Greek symbol. Furthermore, it is written in small d.

The density, mass, and volume are related to each other. These quantities do not change with the change in the quantity of the substance. If we take the large weight or quantity of substance, the density of the substance does not change.

Thus, the correct option is C. The density will remain the same because mass and volume will remain the same.

To learn more about density, refer to the link:

https://brainly.com/question/15164682

#SPJ6

Answer:

Fluere

i hope this helps!

Answer:

The concentration of this solution in units of pounds per gallon is [tex]2.776*10^{-5} \frac{lb}{gal}[/tex]

Explanation:

Units of measurement are established models for measuring different quantities. The conversion of units is the transformation of a quantity, expressed in a certain unit of measure, into an equivalent one, which may or may not be of the same system of units.

In this case, the conversion of units is carried out knowing that 1 μg are equal to 2.205*10⁻⁹ Lb and  1 mL equals 0.00022 Gallons. So

[tex]2.77 \frac{ug}{mL} = \frac{2.77 ug}{mL}[/tex]

If 1 μg equals 2.205*10⁻⁹  lb, 2.77 μg how many lb equals?

[tex]lb=\frac{2.77ug*2.205*10^{-9}lb }{1ug}[/tex]

lb=6.10785*10⁻⁹

So, 2.77 μg= 6.10785*10⁻⁹ lb

Then:

[tex]2.77 \frac{ug}{mL} = \frac{2.77 ug}{mL}=\frac{6.10785*10^{-9}lb }{mL} =\frac{6.10785*10^{-9}lb }{0.00022 gal} =\frac{6.10785*10^{-9}lb }{0.00022 gal}[/tex]

You get:

[tex]2.77 \frac{ug}{mL} = 2.776*10^{-5} \frac{lb}{gal}[/tex]

The concentration of this solution in units of pounds per gallon is [tex]2.776*10^{-5} \frac{lb}{gal}[/tex]

Answer:

3CaBr2 + 2LI3PO4 - > Ca3(PO4) 2 + 6LiBr

Explanation:

The first one I did was PO4. There are two on the right side, so I added 2 to Li3PO4 on the other side. That balanced the PO4s and then gave me 6 Lithiums so I balanced that one next on the right side. I added 6 to LiBr which balanced the Li but then gave me 6 Br, so I finished it off by adding 3 in front of CaBr2 which balanced the calcium and bromines.

Here was the process:

CaBr2+2Li3PO4 -> Ca3(PO4)2+LiBr

Balances PO4 (2on both sides)

CaBr2+2Li3PO4 -> Ca3(PO4)2+6LiBr

Balances Lithiums (6 on each side)

3CaBr2+2Li3PO4 -> Ca3(PO4)2+6LiBr

Balances Calciums and Bromines (3 Calciums and 6 Bromines each side)

Hope this helped!