How many grams of calcium chloride will be needed to make 750 mL of a 0.100 M CaCl2 solution?​

Answers

Answer 1

Answer:

Molarity or molar concentration is the number of moles of solute that can be dissolved in 1 L of a solution.

Molarity = Number of solute (in moles) / Volume of solution (in liters), or

C = n / V

According to the question,

V = 750 ml and C = 0.100 M

For this, let us convert ml into liters

We know 1 L = 1000 ml

Hence, 750 ml = (750/1000) L = 0.75 L

So, V = 0.75 L

We know that C = n / V

So, n = C x V

n = 0.100 x 0.75 = 0.075

n is the number of moles of solute.

Hence, number of moles of CaCl2 = 0.075 moles

That means there are 0.075 moles of CaCl2 in 750 ml of solution.

In order to determine the mass of CaCl2 in grams, we need to know the molar mass of CaCl2.

For this, we need to find out the atomic mass of each atom (by referring the periodic table).

CaCl2 has 1 Ca atom and 2 Cl atoms.

Atomic mass of

Ca = 40.08 g

Cl = 35.45, Cl2 means 2 x 35.45 = 70.90 g

Adding these values, we get mass of CaCl2 in grams.

Hence, mass of CaCl2 = 40.08 + 70.90 = 110.98 g

Thus, 1 mole of CaCl2 weighs 110.98 g.

Hence, 0.075 moles of CaCl2 will weigh

0.075 x 110.98 = 8.3235 g, rounded to 8.32 g

So restating the question, we can say that 8.32 grams of CaCl2 will be needed to make 750 ml of a 0.100 M CaCl2 solution.

HOPE THIS HELPS ❤✌


Related Questions

Molly just started a new job. She needs to fill out a _____ so that her employer knows how much tax to take out. 1099 form tax return form W-4 form W-2 form

Answers

Answer:

The answer is "W-4 form".

Explanation:

The W-4 form is part of the Internal Revenue Service tax form, which is used to submitted by the U.S. government form the customer to information and his or her tax situation. This form informs the customer of the right amount of tax to deduct from his or her salary.

That's why she filled out a W-4 form and know-how often tax he will subtract in the payroll depending on provisions dealing, dependents, potential tax deductions, and credits, etc.

Round to 4 significant figures.
35.5450

Answers

Answer:

35.5450 will be rounded to 35.55

Explanation:

=35.5450

if the last digit is less than 5 then it will be ignored

=35.545

when the dropping digit is 5 then the retaining digit will increse by a factor of 1

=35.55

i hope this will help you

Answer:

35.5450 to 4 significant figures is 35.55

Hope this helps.

Why would an unstable radioactive isotope (nuclide) emit a beta particle (high energy electron)?
A)It has too many neutrons
B)It has too many protons
C)It has too many electrons
D)It has too few electrons

Answers

Answer:

A)It has too many neutrons

Explanation:

Electrons are emitted from the nucleus when a neutron is converted to a proton, an electron and a neutrino. This process is popularly known as beta emission. It reduces the neutron-proton ratio of a nuclide. The neutrino is a particle of zero mass and zero charge that carries off the excess energy and balances spins.

The loss of an electron from the nucleus occurs when there are too many neutrons in the nucleus. The process of beta emission usually reduces the number of neutrons in an atom thereby decreasing the neutron-proton ratio.

Insulin is a protein that is used by the body to regulate both carbohydrate and fat metabolism. A bottle contains 225 mL of insulin at a concentration of 30.0 mg/mL . What is the total mass of insulin in the bottle?

Answers

Answer:

13,000 mg

Explanation:

40mg for every mL so you take 40x325 to wind up with 13,000mg of insulin or 13 grams.

Ethanol, C2H5OH, is considered clean fuel because it burns in oxygen to produce carbon dioxide and water with few trace pollutants. If 325.0 g of H2O are produced during the combustion of ethanol, how many grams of ethanol were present at the beginning of the reaction?

Answers

Answer:

277.8 grams of ethanol

Explanation:

C2H5OH(l)+3O2(g)⟶2CO2(g)+3H2O(l)

It is important to understand that before we can proceed with solving any problem that has to do with stoichiometry, we must first note down the correct and balanced chemical reaction equation.

Number of moles of water formed= mass of water/ molar mass of water

Molar mass of water = 18gmol-1

Number of moles of water = 325g/18 gmol-1= 18.1 moles of water

From the balanced reaction equation;

1 mole of ethanol yields 3 moles of water

x moles of ethanol yields 18.1 moles of water

Hence;

x= 18.1 × 1 / 3 = 6.03 moles of ethanol

Molar mass of ethanol= 46.07 g/mol

Therefore mass of ethanol originally present= 6.03 moles × 46.07 g/mol = 277.8 grams of ethanol

balance
KClO3 ⟶ KCl + O2

Answers

Answer:

[tex]2KCl O_3 \to 2KCl + 3O_2[/tex]

Explanation:

Balance both sides.

Kostya randomly chooses a number from 1 to 10. What is the probability he chooses a number less than 5?

A. 1/2
B. 4/9
C. 2/5
D. 3/5​

Answers

A. 1/2

Explanation- There is a 5/10 chance of choosing on of the numbers which simplifies to 1/2
It’s A. 1/2 -Correct answer.

3. The volume of a gas is reduced from 4 L to 0.5 L while the temperature is held
constant. How does the gas pressure change?

Answers

Answer:

The new pressure is 8 times the original pressure.

Explanation:

Data obtained from the question include:

Initial volume (V1) = 4L

Final volume (V2) = 0.5L

Initial pressure (P1) = P

Final pressure (P2) =..?

The new pressure can be obtained by using the Boyle's law as shown below:

P1V1 = P2V2

P x 4 = P2 x 0.5

Divide both side by 0.5

P2 = P x 4 / 0.5

P2 = 8P

Therefore, the new pressure is 8 times the original pressure.

Calculate the theoretical yield and percent yield for this experiment

Answers

Answer:

A. Theoretical yield of KCl is 36.49g

B. Percentage yield of KCl is 90.4%

Explanation:

The balanced equation for the reaction is given below:

2KCLO3 —> 2KCl + 3O2

Next, we shall determine the mass KClO3 that decomposed and the mass KCl produce from the balanced equation. This is illustrated below:

Molar mass of KClO3 = 39 + 35.5 + (16x3) = 122.5g/mol

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

Molar mass of KCl = 39 + 35.5 = 74.5g/mol

Mass of KCl from the balanced equation = 2 x 74.5 = 149g.

From the balanced equation above,

245g of KClO3 decomposed to produce 149g of KCl.

A. Determination of the theoretical yield of KCl. This is illustrated below:

From the balanced equation above,

245g of KClO3 decomposed to produce 149g of KCl.

Therefore, 60g of KClO3 will decompose to produce = (60 x 149)/245 = 36.49g of KCl.

Therefore, the theoretical yield of KCl is 36.49g

B. Determination of the percentage yield of KCl. This can be obtaine as follow:

Actual yield = 33g

Theoretical yield = 36.49g

Percentage yield =..?

Percentage yield = Actual yield /Theoretical yield x 100

Percentage yield = 33/36.49 x 100

Percentage yield of KCl = 90.4%

Select the word or phrase from the drop-down menu to describe ionic compounds. A formula unit represents the simplest ratio of elements in a of an ionic compound. A crystal is made up of There are two magnesium ions for every two sulfide ions in magnesium sulfide. The ratio of Mg to S in the formula unit is .

Answers

Answer:

A formula unit represents the simplest ratio of elements in a  

✔ crystal

of an ionic compound.

A crystal is made up of  

✔ many atoms that are arranged in a regular pattern.

There are two magnesium ions for every two sulfide ions in magnesium sulfide. The ratio of Mg to S in the formula unit is  

✔ 1:1

.

Explanation:

did it on edge 2020

In a crystal of an ionic compound, a formula unit denotes the most basic elemental ratio.

What do you mean by ionic compound?

Ions, which have positive and negative charges respectively, are the building blocks of ionic compounds, which are neutral substances.

In a crystal of an ionic compound, a formula unit denotes the most basic elemental ratio.

A crystal is composed of several atoms that are organised in a predictable way.

In magnesium sulphide, there are two magnesium ions for every two sulphide ions. The formula unit has a 1:1 Mg to S ratio.

To learn more about ionic compounds, refer to the below link:

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What color would you expect a weak base to turn the paper?

Answers

I believe a weak base would turn the litmus paper blue

What is the molar mass of Ca(OH)2?
a
b
57.008 g/mol
74.092 g/mol
73.080 g/mol
73.088 g/mol
Ос
d

Answers

Answer: the molar mass is 74.092 g/mol

Explanation:

Which of the following samples contains the greatest number of atoms?
a. 9 mole of CO2 b. 10 moles of Xe
c. 11 moles of N2O d. 12 moles of CO

Answers

Answer:

C. 11 moles of N2O

Explanation:

A. CO2 exists as a molecular compound. The number of atoms present = 1 atom of Carbon and 2 atoms oxygen = 3 atoms * 9 = 18 atoms

B. Xe exists as an atom. Number of atoms present = 10 * 1 atom = 10 atoms

C. N20 contains 3 atoms; 2 atoms of Nitrogen and 1 atom of oxygen.

Number of atoms present = 3 * 11 = 33 atoms

D. CO contains 2 atoms, 1 each of carbon and oxygen.

Number of atoms present = 12 * 2 = 24 atoms

Quickly Please!!!!!!

1. How many moles of a gas are contained in a 101 liter flask at a pressure of 2.0 atm and a temperature of 600K? (R = 0.0821)


G

U

E

S

S

Answers

Answer:

[tex]n=4.1mol[/tex]

Explanation:

Hello,

In this case, we can use the ideal gas equation:

[tex]PV=nRT[/tex]

So we know the temperature, pressure and volume, therefore we can easily compute the required moles as shown below:

[tex]n=\frac{PV}{RT}=\frac{2.0atm*101L}{0.082\frac{atm*L}{mol*K}*600K} \\\\n=4.1mol[/tex]

Best regards.

Answer:

4.1 moles

Explanation:

The following data were obtained from the question.

Number of mole (n) =..?

Volume (V) = 101L

Pressure (P) = 2atm

Temperature (T) = 600K

Gas constant (R) = 0.0821atm.L/Kmol

The number of mole of the gas can be obtained by using the ideal gas equation as illustrated below:

PV = nRT

2 x 101 = n x 0.0821 x 600

Divide both side by 0.0821 x 600

n = (2x 101) / (0.0821 x 600)

n = 4.1 moles.

Therefore, the number of mole of the gas in the container is 4.1 moles

4HCl(g) + Si (s) ⇌ SiCl4 (l) + 2H2 (g) would be classified as a(n):

Answers

Answer:

it will be classical as gas

Which fourth-period element, X, forms the compound Lewis structure of the molecule X O 3. The X atom is central with three oxygen atoms connected by double bonds. Each oxygen atom has two lone pairs of electrons. As Br Kr Ga Ge Se

Answers

Answer:

Ga

Explanation:

The fourth period element that is able to form a compound whose lewis structure is XO3 with X as the central atom and three oxygen atoms must be an element in group thirteen in the periodic table.

Gallium is known to form a trioxo- compound in which all gallium atoms are connected to oxygen atoms via double bonds. We don't have this type of compound formed by any other atom listed among the options hence the answer given above. The compound is written as GaO3.

The central atom is a gallium atom, which has the symbol Ga.

We can arrive at this answer because:

According to the octet rule, an atom must have 8 electrons in the valence layer to achieve electrical stability.These atoms can achieve this stability through covalent or ionic bonds.According to the above question, we can state that an X atom received 6 electrons, as three oxygen atoms shared 2 atoms each with the X atom.In this case, the atom x must have 2 atoms in the valence layer, to reach 8 atoms with the bonds it made with the oxygens.

Among the response options, Ga is the only one that has 2 electrons in the valence layer, being able to form bonds with oxygen.

More information:

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If your weight is 120 pounds
and your mass is 54 kilograms, how would those
values change if you were on the moon? The grav-
itational force on the moon is 1/6 the gravitational
force on Earth.​

Answers

Explanation:

Weight is 120 pounds and mass is 54 kg

The mass of an object is same everywhere. If we were on the moon, its mass will remain to be 54 kg.

Weight of an object is given by :

[tex]W=m\times g[/tex]

g is acceleration due to gravity on that surface

For moon, it is 1/6 the gravitational  force on Earth, g = 1.63 m/s²

1 pound = 4.45 N

It means my weight is 533.78 N

On the surface of Moon is will be :

[tex]W=\dfrac{533.78}{1.63}\\W=327.47\ N[/tex]

Main group elements have valence electrons in which suborbitals? Question 5 options: A) d and f B) s and d C) p and f D) s and p

Answers

Answer:

s and p

Explanation:

The main group elements includes elements in Groups 1-2 and Groups 13-18. Groups 1-2 on the periodic table are the s block elements which means the valence electrons are located in the s suborbital. Groups 13-18 on the periodic table are the p block elements which means the valence electrons are located in the s and p orbitals.

PLZ HELP For the reaction: 2NO2(g) → N2O4(l),
the ΔH of the reactants, two moles of NO2 (g), is + 66 kJ/mol,
and the ΔH of the products, N2O4 (l), is -20 kJ/mol.
Which of the following shows the ΔH (change in enthalpy) for the reaction as a whole?

Question 8 options:

ΔrxnH =(- 20 kJ/mol) / (+66 kJ/mol)


ΔrxnH = (+66 kJ/mol) + (- 20 kJ/mol)


ΔrxnH =(-20 kJ/mol) - (+ 66 kJ/mol)


ΔrxnH =(+66 kJ/mol) - (- 20 kJ/mol)

Answers

Answer: [tex]\Delta H_{rxn}=-20kJ/mol-(+66kJ/mol)[/tex]

Explanation:

Heat of reaction or enthalpy change is the energy released or absorbed during the course of the reaction.

It is calculated by subtracting the enthalpy of reactants from the enthalpy of products.

[tex]\Delta H=H_{products}-H_{reactants}[/tex]

[tex]\Delta H[/tex] = enthalpy change = ?

[tex]H_{products}[/tex] = enthalpy of products

[tex]H_{reactants}[/tex] = enthalpy of reactants

For the given reaction :

[tex]2NO_2(g)\rightarrow N_2O_4(l)[/tex]

[tex]\Delta H=H_{N_2O_4}-2\times H_{NO_2}[/tex]

[tex]\Delta H=-20kJ/mol-(+66kJ/mol)[/tex]

does anyone know the answer???​

Answers

Yes the correct answer is 3.14
Yes the correct answer is 3.14

What is the formula for this ionic compound and tha name ?

Answers

Explanation:

K3P = Potassium phosphide


Balance this equation. If a coefficient of "1" is required, choose "blank" for that box.
____ CH 4 + ___ O 2 → ____ CO 2 + ____ H 2 O

Answers

1 CH 4 + 2 O2 = 1 CO2 + 2 H2O

Answer:

CH4 + 2O2 → CO2 + 2H2O

Explanation:

CH4 + O2 → CO2 + H2O

Left Side

C = 1

H = 4

O = 2

Right Side

C = 1

H = 2

O = 3

Ok so we'll balance the H first

CH4 + O2 → CO2 + 2H2O

Left Side

C = 1

H = 4

O = 2

Right Side

C = 1

H = 4

O = 4

Now we'll balance the O

CH4 + 2O2 → CO2 + 2H2O

Left Side

C = 1

H = 4

O = 4

Right Side

C = 1

H = 4

O = 4

When writing the shorthand notation for sulfur, S, which element would you put in brackets?

Answers

You would put Neon, Ne, in Brackets.

The following reaction is at equilibrium. What would be the effect of adding an excess of N2 and O2?
N2 + O2 ↔ 2NO

Question 16 options:

The equilibrium will shift to the right.


The equilibrium will shift to the left.


Less product will be produced.


Twice the product will be produced.

Answers

The equilibrium will shift to the right

Answer:

B

Explanation:

Which type of fuel can only be used in certain geographic area? A. natural gas B. nuclear C. solar D. Biomass

Answers

Answer:

Solar

Explanation:

Ap e x

The type of fuel which can only be used in certain geographic area is nuclear fuel.

What is fuel?

The substance which on reacting with other materials will produces energy in the form of thermal energy and heat will be known as fuels.

Natural gas, solar energy and biogas fuel provides acceptable amount of energy which never causes harm to the environment then they all will be used in all areas.

Nuclear fuels produces a tremendous amount of energy which has an ability to destroy many lives and environment, so it would be used only is those geographical area where no lives are living.

Hence, nuclear fuel can only be used in certain geographic area.

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Which topic is commonly used to explain activation energy and how chemical reactions happen? reaction rate collision theory velocity distribution spontaneous reaction

Answers

Answer: Collision Theory

Collision theory

B. in edge

4. How many grams of ammonium carbonate are needed to decompose in order to produce


6.52g of carbon dioxide? Ammonium oxide is the other product.


(NH4)2(CO,) – (NH4)2O + CO2

Answers

Answer:

14.23g of (NH4)2CO3

Explanation:

We'll begin by writing the balanced equation for the reaction.

(NH4)2CO3 –> (NH4)2O + CO2

Next,, we shall determine the mass of (NH4)2CO3 that decomposed and the mass of CO2 produced from the balanced equation. This is illustrated below:

Molar mass of (NH4)2CO3 = 2[14+(4x1)] + 12 + (16x3)

= 2[14 +4] + 12 + 48

= 2[18] + 60 = 96g/mol

Mass of (NH4)2CO3 from the balanced equation = 1 x 96 = 96g

Molar mass of CO2 = 12 + (2x16) = 44g/mol

Mass of CO2 from the balanced equation = 1 x 44 = 44g.

Summary:

From the balanced equation above,

96g of (NH4)2CO3 decomposed to produce 44g of CO2.

Finally, we can determine the mass of (NH4)2CO3 that decomposed to produce 6.52g of CO2 as follow:

From the balanced equation above,

96g of (NH4)2CO3 decomposed to produce 44g of CO2.

Therefore, Xg of (NH4)2CO3 will decompose to produce 6.52g of CO2 i.e

Xg of (NH4)2CO3 = (96 x 6.52)/44

Xg of (NH4)2CO3 = 14.23g

Therefore, 14.23g of (NH4)2CO3 is needed to produce 6.52g of CO2.

When a cube of manganese oxide was added to a solution of hydrogen peroxide, water and oxygen were produced. Manganese oxide
was not used up in the reaction. Which of the following is likely to decrease the rate of the reaction?
Using a larger amount of solution
O Increasing the mass of the cube
O Chilling the hydrogen peroxide solution
O Smashing the cube into pieces

Answers

Answer: chilling the hydrogen peroxide solution

This will Decrease the rate of reaction

Chilling of hydrogen peroxide solution will cause a decrease in the rate of the reaction. The correct option is C.

What is rate of reaction?

The reaction rate or in some other words the rate of reaction is actually the rate at which a chemical reaction takes place.

It is usually classified as proportional to the alter in product concentration per unit time and the decrease in concentration of reactant per unit time. The rates of reaction of different chemical reactions can vary.

The reaction rate is determined by the amount of the reactants, the temperature, and the catalyst.

As in the given reaction, the cube of manganese oxide was added to a solution of hydrogen peroxide, water and oxygen were produced. Manganese oxide was not used up in the reaction.

By chilling the hydrogen peroxide, the reaction will get altered as the temperature will not be appropriate for the reaction.

Thus, the correct option is C.

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HELP HELP HELP HELP HELP HELP!!!!!!
Barry is 62 years old. He runs every single day. His BMI is 15. He would like to gain weight, and increase muscle in his upper body, chest, and back.
what exercise should he do?

Answers

Answer:

He should eat fruits and vegetables and also skip

ASAP PLEASE !!
What are some factors that causes the actual reaction enthalpy to vary from the accepted reaction enthalpy?

Answers

Answer:

Well, Here's some factors:

The concentrations of the reactants and the products.

The temperature of the system.  

And, The partial pressures of the gases involved.

Good Luck!~

temperatures Pressure
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