what is the mass of insoluble calcium phosphate produced from .555 grams of calcium chloride​

Answers

Answer 1

Answer:

0.518 g

Explanation:

Step 1: Write the balanced equation

3 CaCl₂ + 2 H₃PO₄ ⇒ Ca₃(PO₄)₂ + 6 HCl

Step 2: Calculate the moles corresponding to 0.555 g of CaCl₂

The molar mass of CaCl₂ is 110.98 g/mol.

0.555 g × 1 mol/110.98 g = 5.00 × 10⁻³ mol

Step 3: Calculate the moles of Ca₃(PO₄)₂ produced

5.00 × 10⁻³ mol CaCl₂ × 1 mol Ca₃(PO₄)₂/3 mol CaCl₂ = 1.67 × 10⁻³ mol Ca₃(PO₄)₂

Step 4: Calculate the mass corresponding to 1.67 × 10⁻³ moles of Ca₃(PO₄)₂

The molar mass of Ca₃(PO₄)₂ is 310.18 g/mol.

1.67 × 10⁻³ mol × 310.18 g/mol = 0.518 g


Related Questions

Ethylene glycol flows at 0.01 kg/s through a 3-mm diameter, thin-walled tube. The tube is coiled and submerged in well-stirred water bath maintained at 25°C. If the fluid enters the tube at 85°C, what heat rate and tube length are required for the fluid to leave at 35°C?

Answers

Answer:

heat rate= 1281W

length = 15.8m

Explanation:

we have this data to answer this question with

Tmi = 85 degrees

Tmo = 35 degrees

Ts = 25 dgrees

flow rate = 25 degrees

using engine oil property from table a-5

Tm = Tmo - TMi/2 = 333k

u =0.522x10⁻²

k = 0.26

pr = 51.3

cp = 2562 J/kg.k

mcp(Tmo-Tmi) =

0.01 x 2562(35-85)

= 1281 W

we find the change in Tim

= [(35-25)-(85-25)]/ln[(35-25)/(85-25)]

= -50/ln0.167

= -50/-1.78976

= 27.9°c

we finf the required reynold number

4x0.01/πx0.003x0.522x10⁻²

= 0.04/0.00004921

= 812.8

= 813

we find approximate correlation

NuD = hd/k

NuD = 3.66

3.66 = 0.003D/0.26

cross multiply

0.003D = 3.66x0.26

D = 3.66x0.26/0.003

= 317.2

As = 1281/317x27.9

= 0.145

As = πDL

L = As/πD

= 0.145/π0.003

= 0.145/0.009429

L = 15.378

Which of the following statements is correct concerning the reaction 2 A + B → 2 C + 2 D?


1. The reaction is second-order overall

2. The reaction is third order overall

3. The rate is equal to k[A]²[B]

4. The rate is equal to k[A][B]

5. It cannot be determined given this information

Answers

Answer:

2.The reaction is third order overall

Explanation:

THIS ANSWER IS CORRECT

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In an exothermic reaction, reactants are __ products.
a more stable than
b equal to
c equally stable as
d less stable than

Answers

Answer:

Less stable

Explanation:

When an exothermic reaction occurs, the reactants have a greater energy level than the outputs. The products, in other respects, are more stable than that of the reactants.

The outcomes of an exothermic reaction have a lower energy to react. The enthalpy of a process is the difference between some of the activation energy and the power of the products. 

determine the mass in grams of 3.75 x 10^21 atoms of zinc. (the mass of one mole of zinc is 65.39 g)

Answers

Answer: The mass in [tex]3.75 \times 10^{21}[/tex] atoms of zinc is 0.405 g.

Explanation:

Given: Atoms of zinc = [tex]3.75 \times 10^{21}[/tex]

It is known that 1 mole of every substance contains [tex]6.022 \times 10^{23}[/tex] atoms. So, the number of moles in given number of atoms is as follows.

[tex]Moles = \frac{3.75 \times 10^{21}}{6.022 \times 10^{23}}\\= 0.622 \times 10^{-2}\\= 0.0062 mol[/tex]

As moles is the mass of a substance divided by its molar mass. So, mass of zinc (molar mass = 65.39 g/mol) is calculated as follows.

[tex]Moles = \frac{mass}{molar mass}\\0.0062 mol = \frac{mass}{65.39 g}\\mass = 0.405 g[/tex]

Thus, we can conclude that the mass in [tex]3.75 \times 10^{21}[/tex] atoms of zinc is 0.405 g.

Which safety feature works to slow down nuclear-fission chain reactions?
A. Proliferation
B. Control rods
C. Cooling rods
D. Fuel rods

Answers

Answer:

The answer is

-control rods

Answer:

B. Control Rods.... via A P E X

For the molecular compound dioxygen difluoride , what would you multiply "grams of O2F2 " by to get the units "molecules of O2F2 "

Answers

Answer:

Molecules of O₂F₂ = mass of O₂F₂ × (1 mole O₂F₂ / 70 g O₂F₂) × (6.02 × 10²³ molecules / one mole of O₂F₂)

Explanation:

The Avogadros constant gives the the number of specified entities in one mole of a substance. One mole of any substance contains 6.02 × 10²³ particles. Therefore, one mole of O₂F₂ contains 6.02 × 10²³ molecules.

Also, the molar mass of a substance is the mass in grams of one mole of that substance. It is obtained by summing the relative atomic masses of all the atoms of the elements in the substance. For O₂F₂, the molar mass = (2 × 16 + 2 × 19) g/mol = 70 g/mol

Converting to molecules of O₂F₂;

To convert from grams of a substance to molecules of that substance, multiply by the ratio of one mole and mass of one mole, and then by the number of molecules per mole.

Molecules of A = mass of A × (1 mole / mass of one mole) × (6.02 × 10²³ molecules / 1 mole)

Therefore,Molecules of O₂F₂ = mass of O₂F₂ × (1 mole O₂F₂ / 70 g O₂F₂) × (6.02 × 10²³ molecules /one mole of O₂F₂)

Which of the following statements correctly explains why bromination reactions are more selective than chlorination reactions.
a. bromine radical is less stable than chlorine radical, so it is more reactive and less choosy
b. bromine radical is more stable than chlorine radical, so it is more reactive and less choosy
c. bromine radical is more stable than chlorine radical, so it is less reactive and more choosy
d. bromine radical is less stable than chlorine radical, so it is less reactive and more choosy
e. relative radical stability is 3' radicals > 2" radicals> 1 radicals when bromine radicals snatch hydrogens from alkanes, but when chlorine radicals snatch hydrogens the resulting alkyl radical stability is 3 radicals < 2 radicals< 1' radicals

Answers

Answer: A bromine radical is more stable than chlorine radical, so it is less reactive and more choosy.

Explanation:

A chlorine atom being more electronegative in nature is able to attract a hydrogen atom more readily towards itself as compared to a bromine atom.

Since bromine is less electronegative in nature so bromine will be more selective as a hydrogen abstracting agent. As a result, bromine radical is more stable in nature than chlorine radical.

Thus, we can conclude that bromine radical is more stable than chlorine radical, so it is less reactive and more choosy.

Give the following reaction: ammonium nitrate—> dinitrogen monoxide + water.
a.) Write a complete balanced chemical equation.
b.) Calculate the number of molecules of water produced by 11.2g of ammonium nitrate

Answers

Answer:

a) NH₄NO₃ ⇒ N₂O + 2 H₂O

b) 1.69 × 10²³ molecules

Explanation:

Step 1: Write the balanced equation

NH₄NO₃ ⇒ N₂O + 2 H₂O

Step 2: Convert 11.2 g of NH₄NO₃ to moles

The molar mass of NH₄NO₃ is 80.04 g/mol.

11.2 g × 1 mol/80.04 g = 0.140 mol

Step 3: Calculate the moles of H₂O produced

0.140 mol NH₄NO₃ × 2 mol H₂O/1 mol NH₄NO₃ = 0.280 mol H₂O

Step 4: Calculate the number of molecules in 0.280 moles of water

We will use Avogadro's number.

0.280 mol × 6.02 × 10²³ molecules/1 mol = 1.69 × 10²³ molecules

The data shows the number of years that 30 employees worked for an insurance company before retirement. is the population mean for the number of years worked, and % of the employees worked for the company for at least 10 years. (Round off your answers to the nearest integer.)

Answers

Answer:

14

73%

Explanation:

The mean Number of years worked :

. (sum of service years) / employees in the

(8+13+15+3+13+28+4+12+4+26+29+3+10+3+17+13+15+15+23+13+12+1+14+14+17+16+7+27+18+24) /

(417 / 30)

= 13.9 years

= 14 years

The percentage of employees who have worked for atleast 10 years :

Number of employees with service years ≥ 10 years = 22 employees

Total number of employees

Percentage (%) = (22 / 30= * 100% = 0.7333 * 100% = 73.33% = 73%

A chemist measures the amount of iodine solid produced during an experiment. He finds that of iodine solid is produced. Calculate the number of moles of iodine solid produced. Round your answer to significant digits.

Answers

The question is incomplete, the complete question is:

A chemist measures the amount of iodine solid produced during an experiment. He finds that 8.31 g of iodine solid is produced. Calculate the number of moles of iodine solid produced. Round your answer to the correct number of significant digits.

Answer: The number of moles of solid iodine produced is 0.0327 moles

Explanation:

The number of moles is defined as the ratio of the mass of a substance to its molar mass.  The equation used is:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)

Given mass of solid iodine = 8.31 g

Molar mass of solid iodine = 253.8089 g/mol

Plugging values in equation 1:

[tex]\text{Moles of solid iodine}=\frac{8.31g}{253.8089g/mol}=0.0327mol[/tex]

Hence, the number of moles of solid iodine produced is 0.0327 moles

In order for a substitution reaction to take place, at a minimum, __________ and ___________ are needed. carbocation rearrangement proton transfer loss of a leaving group nucleophilic attack

Answers

Answer: In order for a substitution reaction to take place, at a minimum, loss of a leaving group and nucleophilic attack are needed.

Explanation:

When one group in a molecule is replaced by another one then it is called a substitution reaction.

For a substitution reaction reaction to occur at a minimum, it is necessary to have a leaving group that helps in creating a carbocation and hence a nucleophile can easily attack.

For example, [tex]CH_{4} + Cl_{2} + h\nu \rightarrow CH_{3}Cl + HCl[/tex]

Thus, we can conclude that in order for a substitution reaction to take place, at a minimum, loss of a leaving group and nucleophilic attack are needed.

A. Directions:Describe ways on how to protect humans and plants and animals Choose your answer in the box and fill in the concept map below​

Answers

Answer:

i) Humans - drinks lot of water

- use umbrella

- use hats and sunglasses

- apply sunblock when swimming

- wear rush guard

ii) Plants - water the plants

-put a shade on the plants

iii) Animals - provide pets with plenty of water

- place the animals under the tree during noon time

A soluble unknown has contaminated your sample. It absorbs the same wavelength as your analyte, Allura Red dye. How will this affect your results, and what type of error is introduced

Answers

Answer:

The explanation as per the given query is presented in the following paragraph.

Explanation:

The Allura Reds Pigment or coloring increases the absorption by absorbing at around a very similar wavelength as that of the analysis.Therefore, the approximated analysis concentration or its intensity seemed substantially higher than that of the authentic one. Some positive mistake is going to exist.

Thus the above is the correct explanation.

The measured absorbance will be higher, thereby creating systematic error.

Absorbance can be defined as the value or quantity of light absorbed by a given sample.

The presence of impurity with a similar absorption wavelength will increase the absorbance.

Moreover, systematic error is a type of error that is repeated along with different processes of measurement.

In conclusion, the measured absorbance will be higher, thereby creating systematic error.

Learn more in:

https://brainly.com/question/14919298

Draw bond-line formulas of all dichloro derivatives that might be formed when 1-chloro-2,2,3,3,-tetramethylpentane is allowed to react with Cl 2 under UV irradiation. For each structure, indicate, with an asterisk, any stereocenters that might be present. Predcit the percentage of each product using the relative reactivities 3 0 = 5.3, 2 0 = 3.6, 1 0 = 1

Answers

Answer:

Explanation:

This is a halogenation reaction i.e substitution or replacement of a single or more than a single hydrogen atom in the organic alkane compound with the halogen(here it is chlorine).

The chlorination of 1-chloro-2,2,3,3-tetramethylpentane under UV light resulted in the formation of five (5) dichloro derivatives which are shown in the image attached below.

Also, the compounds containing a stereocenter (i.e a location within the compound composing of various substituents in which the interchangeability of these substituents has the tendency of resulting into a stereoisomer) are indicated with an asterisk in the image below.

From the image below:

compound 1 ⇒  1,1-dichloro-2,2,3,3-tetramethylpentane = 2° C

The given relative reactivity rate for 2°  = 3.6x

For compound 2 ⇒  1,4-dichloro-2,2,3,3-tetramethylpentane = 2°  = 3.6x

For compound 3 ⇒ 1,5-dichloro-2,2,3,3-tetramethylpentane = 1°  = 1x

For compound 4 ⇒ 1-chloro-2-chloromethyl-2,3,3-trimethylpentane

= 1°  = 1x

For compound 5 ⇒ 1-chloro-3-chloromethyl-2,2,3-trimethylpentane

= 1°  = 1x

As such, we have:

2(3.6x) + 3(1x) = 100

7.2x + 3x = 100

10.2x = 100

x = 100/10.2

x = 9.803°

For compound (1) = 3.6(9.803) = 35.3%

For compound (2) = 3.6(9.803) = 35.3%

For compound (3) = 1(9.803) = 9.803°%

For compound (4) = 1(9.803) = 9.803°%

For compound (5) = 1(9.803) = 9.803°%

Calculate the moles of H3PO4 that reacted (8). Consult the coefficients in the balance chemical reaction to obtain the mole ratio. Show your calculation here.

Answers

Answer:

The number of moles of H₃PO₄ that reacted is 0.000343 moles

Note: Some data is missing. Data from the attachment is used for the calculationsinnthe explanation below.

Explanation:

The reaction is a neutralization reaction between NaOH and H₃PO₄. The equation of the reaction is given as follows:

3 NaOH + H₃PO₄ ---> Na₃PO₄ + 3 H₂O

The molarity of the NaOH solution is 0.238 mol/L.

Average volume of NaOH used during the titration to arrive to endpoint = (4.6 + 3.9 + 4.5) mL / 3 = 4.33 mL

Molarity is defined ratio of the number of moles of solute to the volume of solution. Mathematically, molarity = number of moles/volume in Litres

Number of moles of NaOH reacted = 0.238 mol/L × (4.33mL × 1 L/1000 mL)

Number of moles of NaOH = 0.00103 moles

From the equation of the reaction, 3 moles of NaOH reacts with 1 mole of H₃PO₄

0.00103 moles of NaOH will react with 0.00103 x 1/3 moles of H₃PO₄ = 0.000343 moles of H₃PO₄.

Therefore, number of moles of H₃PO₄ that reacted is 0.000343 moles

Gaseous methane will react with gaseous oxygen to produce gaseous carbon dioxide and gaseous water . Suppose 9.6 g of methane is mixed with 64.9 g of oxygen. Calculate the maximum mass of water that could be produced by the chemical reaction. Round your answer to significant digits.

Answers

Answer:

21.6 g

Explanation:

The reaction that takes place is:

CH₄ + 2O₂ → CO₂ + 2H₂O

First we convert the given masses of both reactants into moles, using their respective molar masses:

9.6 g CH₄ ÷ 16 g/mol = 0.6 mol CH₄64.9 g O₂ ÷ 32 g/mol = 2.03 mol O₂

0.6 moles of CH₄ would react completely with (2 * 0.6) 1.2 moles of O₂. As there are more O₂ moles than required, O₂ is the reactant in excess and CH₄ is the limiting reactant.

Now we calculate how many moles of water are produced, using the number of moles of the limiting reactant:

0.6 mol CH₄ * [tex]\frac{2molH_2O}{1molCH_4}[/tex] = 1.2 mol H₂O

Finally we convert 1.2 moles of water into grams, using its molar mass:

1.2 mol * 18 g/mol = 21.6 g


Which atomic model states that it is impossible to know the exact location of electrons around the nucleus?

Answers

Answer:

Bohr Model is the correct answer

Answer:

Electron -Cloud Model

Explanation:

Just took the quiz got 100%

what does LPG stand for? mention one important source of LPG give sort answer​

Answers

Answer:

liquefied petroleum gas

LPG is prepared by refining natural gas. it is made by refining crude oil or from extracted natural gas streams as they emerge from the ground.

classify each of the following as a pure substance or a mixture.
a) baking soda
b) ice
c)blueberry muffin
d) zink

Answers

Baking soda- mixture (I think)
Ice- purse substance
Blueberry muffin- mixture
Zink- mixture

Answer:

c

Explanation:

its c because it has multiple mixture blueberries flower water and others thats why i says c

The tools shown in the diagram are used for gardening Each tool is made up
of two levers that are attached to each other. The handles are the input arms,
and the cutting blades are the output armo
Hand shears
Lopper
Which tool has a greater mechanical advantage, and why?
A. The lopper, because the input work is the same as the output work
B. The hand shears, because their shorter handles transfer force
more quickly to the cutting blade
C. The hand shears, because you can apply less total force to the
handles with one hand
D. The lopper, because its longer handles can produce more output
force with less input force

Answers

Answer:

D

Explanation:

The longer handles distribute the force across a longer distance.

A cylinder contains 26.5 L of oxygen gas at a pressure of 1.7 atm and a temperature of 280 K. How much gas (in moles) is in the cylinder?

Answers

Answer:

The appropriate answer is "1.96 mol".

Explanation:

The given values are:

Volume,

V = 26.5 L

Pressure,

P = 1.7 atm

Temperature,

T = 280 K

Now,

The number of moles (n) will be:

= [tex]\frac{PV}{RT}[/tex]

By substituting the values, we get

= [tex]\frac{1.7\times 26.5}{0.0821\times 280}[/tex]

= [tex]\frac{45.05}{22.988}[/tex]

= [tex]1.96 \ mol[/tex]

pls help ive been stuck on this question for a while im not good with chemistry lol.

Answers

Answer:

The answer would be B, putting thermal energy into something means you're adding heat into it.

Sugar is added to water and initially completely dissolves, but eventually solid sugar collects on the bottom of the container. Sugar and water are ________partially miscible . This produces a dynamic equilibrium. Ethanol (a liquid) is added to water and only a single layer is observed no matter how much ethanol is added. Ethanol and water are__________

Answers

Answer: Sugar is added to water and initially completely dissolves, but eventually solid sugar collects on the bottom of the container. Sugar and water are both partially miscible. This produces a dynamic equilibrium. Ethanol (a liquid) is added to water and only a single layer is observed no matter how much ethanol is added. Ethanol and water are miscible.

Explanation:

When a substance (solute) dissolves partially in a solvent then it is known as partially miscible in the solvent. In such cases, a small amount of solute remains at the bottom of solution.

If a solute dissolves completely in solvent like water such that only one layer is seen in the solution then it means that the solute is miscible in solvent.

Thus, we can conclude that sugar is added to water and initially completely dissolves, but eventually solid sugar collects on the bottom of the container. Sugar and water are both partially miscible. This produces a dynamic equilibrium. Ethanol (a liquid) is added to water and only a single layer is observed no matter how much ethanol is added. Ethanol and water are miscible.

0.300 moles of sodium nitrite are needed for a reaction. The solution is 0.450 M. How many mL are needed

Answers

Answer:

The solution is 0.450 M. How many mL are needed?

- 0.667 mL

Explanation:

I have 50.00 mL of 0.100 M ethyl amine (C2H5NH2). I gradually add a solution of 0.025 M nitric acid (HNO3) to the ethyl amine solution.

Required:
What is the pH after the addition of a total of 201 mL of the nitric acid?

Answers

Answer:

4.00 is the pH of the mixture

Explanation:

The ethyl amine reacts with HNO3 as follows:

C2H5NH2 + HNO3 → C2H5NH3⁺ + NO3⁻

To solve this question we need to find the moles of ethyl amine and the moles of HNO3:

Moles C2H5NH2:

0.0500L * (0.100mol/L) = 0.00500 moles ethyl amine

Moles HNO3:

0.201L * (0.025mol/L) = 0.005025 moles HNO3

That means HNO3 is in excess. The moles in excess are:

0.005025 moles HNO3 - 0.00500 moles ethyl amine =

2.5x10⁻⁵ moles HNO₃

In 50 + 201mL = 251mL = 0.251L:

2.5x10⁻⁵ moles HNO₃ / 0.251L = 9.96x10⁻⁵M = [H+]

As pH = -log [H+]

pH = -log 9.96x10⁻⁵M

pH = 4.00 is the pH of the mixture

I need help with the practice question at the bottom. Thank you.

Answers

As the gas expands on the surrounding, work is done by the system.

Therefore, W= -279J

Absorbtion of heat,q= +216J

∆U=q+W = (216-279)J= -63J

the pressure of a sample of gas at constant volume is 942 kPa at 338K. what will the pressure be 293k?

Answers

Explanation:

4 tctcgcgcgctctchvvyctctc

Question 1
1 pts
How many mols of bromine are present in 35.7g of
Tin(IV) bromate?

Answers

Answer:

n = 0.0814 mol

Explanation:

Given mass, m = 35.7g

The molar mass of Tin(IV) bromate, M = 438.33 g/mol

We need to find the number of moles of bromine. We know that,

No. of moles = given mass/molar mass

So,

[tex]n=\dfrac{35.7}{438.33}\\\\n=0.0814\ mol[/tex]

So, there are 0.0814 moles of bromine in 35.7g of  Tin(IV) bromate.

Explain the sample prep for IR

Answers

Answer:

) Making a sandwich To prepare a liquid sample to IR analysis, firstly place a drop of the liquid on the face of a highly polished salt plate (such as NaCl, AgCl or KBr), then place a second plate on top of the first plate so as to spread the liquid in a thin layer between the plates, and clamps the plates together.

How many grams of solute are present in 635mL of 0.450 M KBr?

Answers

Answer:

34.03 g

Explanation:

We'll begin by converting 635 mL to L. This can be obtained as follow:

1000 mL = 1 L

Therefore,

635 mL = 635 mL × 1 L / 1000 mL

635 mL = 0.635 L

Thus, 635 mL is equivalent to 0.635 L

Next, we shall determine the number of mole of the solute (KBr) in the solution. This can be obtained as follow:

Volume = 0.635 L

Molarity = 0.450 M

Mole of KBr =?

Mole = Molarity × Volume

Mole of KBr = 0.450 × 0.635

Mole of KBr = 0.286 mole

Finally, we shall determine the mass of 0.286 mole of KBr. This can be obtained as follow:

Mole of KBr = 0.286 mole

Molar mass of KBr = 39 + 80

= 119 g/mol

Mass of KBr =?

Mass = mole × molar mass

Mass of KBr = 0.286 × 119

Mass of KBr = 34.03 g

Thus, the mass of the solute (KBr) in the solution is 34.03 g

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