During the process of diluting a solution, ________.

a. water is removed from the concentrated solution
b. the amount of solvent does not change
c. the amount of solute does not change
d. the volume of the solution does not change
e. there is more solute in the concentrated solution

Answers

Answer 1
A kfjfjdnsndmxkkdnndndnd

Related Questions

28 mL of 0.10 M HCl is added to 60.0 mL of 0.10 M Sr(OH)2. Determine the concentration of OHin the resulting solution.

Answers

Answer:

Explanation:

Sr(OH)₂.+ 2HCl = SrCl₂ + 2H₂O

Moles of HCl in 28mL of .10 M HCl = .028 x .1 = .0028 moles .

Moles of Sr(OH)₂ in 60mL of .10 M Sr(OH)₂ = .060 x .1 = .0060 moles

2 moles of HCl  reacts with 1 mole of Sr(OH)₂

.0028 moles of HCl  reacts with .0014  mole of Sr(OH)₂

moles of Sr(OH)₂ remaining = .0060 - .0014 = .0046 moles .

Sr(OH)₂  = Sr⁺  +  2OH⁻

1 mole                  2 mole

.0046                    .0092

Total volume of solution = 88 mL .

88 mL of solution contains .0092 moles of OH⁻

concentration of OH⁻ = .0092 / .088

= .1045 M  .

When Strontium hydroxide, Sr(OH)₂ will react with hydrochloric acid (HCl) then the reaction formed will be:

Sr(OH)₂+ 2 HCl ⇒ SrCl₂ + 2 H₂O

The concentration of OH in the resulting solution will be 0.1045 M.

This can be calculated by:

Molarity (HCl) = 0.10 M

Volume (HCl) = 28 mL

Molarity (Sr(OH)₂) = 0.10 M

Volume (Sr(OH)₂) = 60.0 mL

[tex]\text{Molarity} = \dfrac{\text{moles}}{\text{volume of the solution in litres}}[/tex]

Moles of HCl = 0.028 x 0.1 = 0.0028 moles

Moles of Sr(OH)₂ =  0.060 x 0.1 = 0.0060 moles

2 moles of hydrochloric acid will react with 1 mole of Sr(OH)₂

So, 0.0028 moles of HCl will react with 0.0014 mole of Sr(OH)₂

Remaining moles of Sr(OH)₂  = 0.0060 - 0.0014 = 0.0046 moles

Sr(OH)₂   ⇒   Sr⁺ + 2OH⁻

1 mole                    2 mole

0.0046                  0.0092

Total volume of solution = 88 mL

88 mL of solution contains 0.0092 moles of OH⁻

Hence, concentration of OH⁻ :

[tex]= \dfrac{0.0092 }{0.088}[/tex]

= 0.1045 M

Therefore, 0.1045 M will be the concentration of OH in the solution.

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A 25.225 g sample of aqueous waste leaving a fertilizer manufacturer contains ammonia. The sample is diluted with 75.815 g of water. A 14.842 g aliquot of this solution is then titrated with 0.1068 M HCl . It required 29.99 mL of the HCl solution to reach the methyl red endpoint. Calculate the weight percent NH3 in the aqueous waste

Answers

Answer:

1.43 (w/w %)

Explanation:

HCl reacts with NH3 as follows:

HCl + NH3 → NH4+ + Cl-

1 mole of HCl reacts per mole of ammonia.

Mass of NH3 is obtained as follows:

Moles HCl:

0.02999L * (0.1068mol / L) = 3.203x10-3 moles HCl = Moles NH3

Mass NH3 in the aliquot:

3.203x10-3 moles NH3 * (17.031g / mol) = 0.0545g.

Mass of sample + water = 22.225g + 75.815g = 98.04g

Dilution factor: 98.04g / 14.842g = 6.6056

That means mass of NH3 in the sample is:

0.0545g * 6.6056 = 0.36g NH3

Weight percent is:

0.36g NH3 / 25.225g * 100

1.43 (w/w %)

A student drew a diagram of the quantum model of an atom, as shown.


A small circle is shown. Six light gray spheres and six dark gray spheres are shown inside the circle. On the outer side of the circle is another circle of larger radius. This circle has two small circle on its boundary. Another circle of even greater radius is on the outside of the second circle. This outermost circle has four small circles on its boundary.


Which of the following explains if the student's diagram is correct or incorrect?


A - The diagram is incorrect because electrons follow an elliptical path instead of a circular path.

B - The diagram is incorrect because the exact location of the electrons cannot be determined.

C - The diagram is correct because protons and neutrons are concentrated at the center of the atom.

D - The diagram is correct because electrons are present in distinct energy levels around the nucleus.

Answers

The diagram is correct because electrons are present in distinct energy levels around the nucleus. Option D

What is the quantum model?

Let nus just take a minute to be able to remind ourselves that when we look at the atom that there are several subatomic particles that can be shown to be able to make up the atom. We know that the electron is the particle that can be shown to be arranged in shells.

What we saw in the inner or the core of the atom is the nucleus and the six grey spheres  that we can see there would have to do with the nucleus of the atom that is in the question.

As we now look up at the shells, we can see the electrons as they have been arranged into the respective shells were they can be found in the atom on the basis of the energy that they possess.

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Question 4 of 5
Most paints include a pigment (the color), a binder (the
glue), and a solvent. The binder makes the paint color stick
to the surface being painted.
Which part of the manufacturing process occurs when binders are added to a
paint mixture?
A. Separating
B. Forming
C. Finishing
D. Combining
SUE

Answers

Answer:

answer is d Combining

Explanation:

I did the test and got it correct

As a chemical change takes place when binders are added to a paint mixture combining part of the manufacturing process occurs.

What are chemical changes?

Chemical changes are defined as changes which occur when a substance combines with another substance to form a new substance.Alternatively, when a substance breaks down or decomposes to give new substances it is also considered to be a chemical change.

There are several characteristics of chemical changes like change in color, change in state , change in odor and change in composition . During chemical change there is also formation of precipitate an insoluble mass of substance or even evolution of gases.

There are three types of chemical changes:

1) inorganic changes

2)organic changes

3) biochemical changes

During chemical changes atoms are rearranged and changes are accompanied by an energy change as new substances are formed.

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show is a pedigree chart. the chart shows that sally is carrier for red-green color blindness​

Answers

Answer:

you cant post pictures on brainly answers.... can you?

Explanation:

can you help me out pleas​

Answers

Answer:a a atom

Explanation:

Answer:

a. carbon

b. atomic number

c. mass number

d. 6

e. 7

f. 8

pls mark as brainliest


6.At a pressure of 5.0 atmospheres, a sample of gas occupies 40 liters. What volume
will the same sample occupy at 1.0 atmosphere?
(a) 50 L
(b) 100 L
O (C) 80 L
(d) 200 L

Answers

Answer:

The answer is 200 L

Explanation:

The new volume can be found by using the formula for Boyle's law which is

[tex]P_1V_1 = P_2V_2[/tex]

where

P1 is the initial pressure

P2 is the final pressure

V1 is the initial volume

V2 is the final volume

Since we are finding the new volume

[tex]V_2 = \frac{P_1V_1}{P_2} \\[/tex]

So we have

[tex]V_2 = \frac{5 \times 40}{1} \\ = 5 \times 40[/tex]

We have the final answer as

200 L

Hope this helps you

What is the compound NH3

Answers

Ammonia is the compound NH3

Describe what a limiting reactant is

Answers

Answer:

The reactant in a chemical reaction that limits the amount of product that can be formed. The reaction will stop when all of the limiting reactant is consumed. Excess Reactant - The reactant in a chemical reaction that remains when a reaction stops when the limiting reactant is completely consumed.

Explanation:

What is the structure of amylopectin?

Answers

Answer:

Not sure if you just wanted the basic structure or full on structure.

Explanation:

How much heat is required to vaporize 15.8 g CH3OH(l) at its boiling point? (∆Hvap = 38.0 kJ/mol) a a. 2.41 kJ b 77.0 kJ c 18.8 kJ d 600. kJ

Answers

Answer:

be.77.0kj.

Explanation:

add moles then times

Considering the definition of enthalpy of vaporization,  the correct answer is option c. the heat required to vaporize 15.8 g of CH₃OH at its boiling point is 18.8 kJ.

When a material changes phase from solid to liquid, or from liquid to gas, a certain amount of energy is involved in this phase change.

In case of phase change from liquid to gas, this amount of energy is known as enthalpy of vaporization (symbolized as ∆H vap), also known as (latent) heat of vaporization or heat of evaporation.

In other words, the enthalpy of vaporization is the amount of energy required to change a unit of mass (for example, moles or kg) of a substance from phase liquid to phase gas at constant temperature and pressure.

In this case, you know that enthalpy of vaporization is ∆Hvap = 38.0 kJ/mol.

On the other side, you want to vaporize 15.8 g of CH₃OH.  Then, being the molar mass of the compound 32 g / mole (that is, the amount of mass contained in one mole), the number of moles to be vaporized is:

[tex]15.8 gramsx\frac{1 mol}{32 grams}= 0.49375 moles[/tex]

Then, the heat required to vaporize 0.49375 moles of CH₃OH at its boiling point is calculated taking into account the enthalpy of vaporization by:

0.49375 moles×  38.0 kJ/mol= 18.76 kJ ≅ 18.8 kJ

Finally, the correct answer is option c. the heat required to vaporize 15.8 g of CH₃OH at its boiling point is 18.8 kJ.

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Which are the products in the equation CH3SH + 4O2 → CO2 + SO2 +2H2O? Check all that apply. CH3SH O2 CO2 SO2 H2O

Answers

To calculate the atoms of an element in a given molecule, we need to multiply stoichiometry by the number that is written on the foot of that element. Therefore, the products are carbon dioxide, sulfur dioxide and water.

What is Balanced equation?

Balanced equation is the one in which the total number of atoms of a species on reactant side is equal to the total number of atoms on product side. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, displacement reaction.

The other characteristic of balanced equation is that physical state should be written with each compound or molecule on reactant and product side. Physical state should be written in brackets. s means solid, l means liquid, g means gas.

The balanced equation is

CH[tex]_3[/tex]SH + 4O[tex]_2[/tex] → CO[tex]_2[/tex] + SO[tex]_2[/tex] +2H[tex]_2[/tex]O

The products that are formed in the given reaction are carbon dioxide, sulfur dioxide and water.

Therefore, the products are carbon dioxide, sulfur dioxide and water.

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Type your answer in decimal form. Do not round.
7 days = hours

Answers

168.0
Hope this helps u
Explanation:
Solar day:
1

day

=
24
h

7

day
=
7

24
h
=
168
h

Stellar day:
1

day

=

23

hours

56

minutes

and

4.1

seconds

=

Which pair of atoms are isotopes ?

Answers

Answer:

If two atoms have different numbers of protons, they are different elements. However, if two atoms have the same number of protons, but different numbers of neutrons we refer to them as isotopes. Two terms we use to identify nuclides (isotopes) are atomic number and mass number.

Explanation:

Your Welcome!

To see the number of atoms of an element in a given molecule we need to multiply stoichiometry to the number that is written on the foot of the element that is stoichiometry. Therefore, in below given ways we can identify isotopes.

What is atom?

Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.

In the nucleus, proton and neutron are present. Electron has -1 charge while proton has +1 charge. Neutron is neutral that is it has no charge. So overall the charge of nucleus is due to only proton, not by neutron.

Differing elements exist when two atoms contain different numbers of protons. If two atoms contain the same amount of protons but differing numbers of neutrons, they are referred to be isotopes.

Therefore, in above given ways we can identify isotopes.

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each substance in a solution mixture is visible to the naked eye? True or False

Answers

False
In a solution mixture, the particles are very small. You won’t be able to see them

Which fossil fuel is made when plants from swamps are covered, pressed, and heated for millions of years? A Coal B Petroleum C Natural Gas D Nuclear

Answers

Answer:

A: COAL

Explanation:

Coal was created hundreds of millions years ago. When prehistoric plant life died and sank to the bottom of the swamp and was covered by layers of sediment.

HElp me plzzzzz??????

Answers

Answer:

The answer to your question is given below

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

Zn + 2HCl —> ZnCl2 + H2

Thus, we can write out the atoms present in both the reactant and the product by doing a simple head count. The atoms present are listed below:

Element >>> Reactant >>> Product

Zn >>>>>>>> 1 >>>>>>>>>> 1

H >>>>>>>>> 2 >>>>>>>>> 2

Cl >>>>>>>>> 2 >>>>>>>>> 2

what is the missing value​

Answers

Answer:

72

Explanation:

The pattern here may be hard to find at first, but it's this: the number in the middle of the triangle = (number at lower left corner of triangle x number at upper vertex of triangle) + (number at upper vertex of triangle x number at lower right corner of triangle).

Thus, for the missing value...

Missing value = (3x8) + (8x6) = 24+48 = 72.

Could you tell me what concept in chemistry relates to this? I'm interested.

Also check out stylesben's answer. Seems like there's several ways of doing this.

Answer:

the answer is 72

Explanation:

6+3=9 and multiply 9 with 8 and answer comes 72

Identify the true statements about introns.a- they code for polypeptide proteinsb- they have a branch site located 20 to 50 nucleotides upstream of the 3' splice sitec- they end with the nucleotides AG at the 3' endd- they begin with the nucleotides GU at the 5' ende- they tend to be common in bacterial genes

Answers

Answer:

The answer is "Option b, c, and d".

Explanation:

In such a gene, Autosomes are also the sequence for code and transposable elements, not the series of encoding. Through the expression of genes, such fragments of its introns are split through protein complexes throughout the translation process. There has been no kenaf fiber in the genomes of prokaryotic cells.

q=m(delta)T Calculate the final temperature reached when 324 J of heat is added to a 22.5g iron bar initially at 20.0 degrees C. The specific heat capacity of iron is 0.45 J/g degrees C.

Answers

Answer:

T(final) = 52°C

Explanation:

1st, you need to correct your heat flow formula => q = mcΔT.

m = 22.5g

c = 0.45 j/g·°C

ΔT = T(final) - T(initial) = T(final) - 20°C

q = (22.5g)(0.45j/g·°C)((final) - 20°C) = 324j

=> T(final) = [324j/(22.5g)(0.45j/g·°C)] + 20°C = 52°C

Just enough 0.500 M HCl is added to 30.0 mL of 2.5 M NH3 to reach the equivalence point. The Kb of NH3 = 1.8 X 10-5
Write the balanced equation for this reaction.




What volume of 0.500 M HCl solution was added?



What is the molarity of the salt produced from the neutralization reaction?




What is the pH of the solution at the equivalence point?

Answers

a.NH₃+HCl⇒NH₄Cl

b.volume HCl=150 ml

c. pH=4.82

Further explanation

Reaction

NH₃+HCl⇒NH₄Cl

The equivalence point⇒mol NH₃=HCl

Titration formula :

M₁V₁n₁=M₂V₂n₂(n=acid base valence, NH₃=HCl=1)

mol NH₃

[tex]\tt 2.5\times 30=75~mlmol[/tex]

mol HCl=75 mlmol

Volume HCl :

[tex]\tt \dfrac{75}{0.5}=150~ml[/tex]

Volume total :

[tex]\tt 150+30=180~ml[/tex]

molarity of salt(NH₄Cl)

mol NH₄Cl=mol NH₃=75 mlmol=0.075 mol

[tex]\tt M=\dfrac{0.075}{0.180}= 0.42[/tex]

pH of solution

Dissociation of NH₄Cl at water to find [H₃O⁺]

[tex]\tt NH_4+H_2O\rightarrow NH_3+H_3O^+[/tex]

ICE at equilibrium :

0.41-x            x        x

Ka(Kw:Kb)= 10⁻¹⁴ : 1.8.10⁻⁵=5.6.10⁻¹⁰

[tex]\tt Ka=\dfrac{NH_3.H_3O}{NH_4}=\dfrac{x^2}{0.41}[/tex]

[H₃O⁺]=x :

[tex]\tt \sqrt{5.6.10^{-10}\times 0.41}=1.515.10^{-5}[/tex]

pH=-log[H₃O⁺]

[tex]\tt pH=5-log~1.515=4.82[/tex]

Based on what you have seen in this gizmo what is the best definition of the doppler effect?

Answers

Answer:

Based on what you have seen in the Doppler Effect Gizmo, what is the best definition of the Doppler effect? A change in the frequency of a wave caused by the motion of the source relative to the observer. The increase in volume of a sound as the source approaches an observer.

Explanation:

23.1 G Of HCI (a Strong Acid) Is Added To Water To Make 1250 ML Of Solution.

Answers

Answer:

[H₃O⁺] = 0.0507 M

pH = 1.29

Explanation:

23.1 g of HCI (a strong acid) is added to water to make 1250 mL of solution. Calculate [H₃O⁺] and pH of the solution.

Step 1: Given data

Mass of HCl (solute): 23.1 gVolume of solution: 1250 mL

Step 2: Calculate the concentration of HCl

We will use the following expression.

[HCl] = mass HCl / molar mass HCl × liters of solution

[HCl] = 2.31 g / 36.46 g/mol × 1.250 L

[HCl] = 0.0507 M

Step 3: Calculate the concentration of H₃O⁺

HCl is a strong acid according to the following equation.

HCl(aq) + H₂O(l) ⇒ H₃O⁺(aq) + Cl⁻(aq)

The molar ratio of HCl to H₃O⁺ is 1:1. Then, [H₃O⁺] = 0.0507 M.

Step 4: Calculate the pH of the solution

We will use the following expression.

pH = -log [H₃O⁺]

pH = -log 0.0507

pH = 1.29

Liquid 1 has a density of 2.0 g/ml, Liquid 2
has a density of 1.5 g/ml, and Liquid 3 has a density of 1.8 g/ml. Which liquidwill make up
the top layer?

Answers

Liquid 2 because the lower the density the more it floats and the higher the density the more it sinks. The order from top to bottom is liquid 2, liquid 3, liquid 1

What type of particles move to create electicity?
electrons
protons
neutrons

Answers

the answer is electrons.....

Answer:

electrons

Explanation:

Determine the acid dissociation constant for a 0.010 M nitrous acid (HNO2) solution that has a pH of 2.70. Nitrous acid is a weak monoprotic acid and the equilibrium equation of interest is:________

Answers

Answer:

HNO₂ ⇄ H⁺ + NO₂⁻

Ka = 4.0 × 10⁻⁴

Explanation:

Step 1: Given data

Concentration of nitrous acid (Ca): 0.010 MpH of the solution: 2.70

Step 2: Write the acid dissociation reaction

Nitrous acid is a weak acid that dissociates according to the following expression.

HNO₂ ⇄ H⁺ + NO₂⁻

Step 3: Calculate the concentration of H⁺

We will use the definition of pH.

pH = -log [H⁺]

[H⁺] = antilog - pH = antilog -2.70 = 2.00 × 10⁻³ M

Step 4: Calculate the acid dissociation constant (Ka)

For a weak acid, we can calculate Ka using the following expression.

Ka = [H⁺]²/Ca

Ka = (2.00 × 10⁻³)²/0.010

Ka = 4.0 × 10⁻⁴

a solution is made by dissolving 25g of nacl in 300g of water. What is the mass percentage

Answers

Answer:

0.83 bar

That is

23/300*100

=0.83 bar

would you like to explore outer space? Why or why not? If you could travel to any part of the galaxy at lightning speed would like to see what is truly out in the universe would you do it? Why or why not?

Answers

Answer:

Yes!

Explanation:

I think It would be fun!, Going thought space going from planet to planet. once i get back to earth i can make a document about my time in space.

a single covalent bond is made up of​

Answers

Answer:

In chemistry, a single bond is a chemical bond between two atoms involving two valence electrons. That is, the atoms share one pair of electrons where the bond forms. Therefore, a single bond is a type of covalent bond.

Explanation:

(copied from Google)

The ion formed by an atom of sulfur when it gains two electrons is called a:

Do not answer cation or anion​

Answers

Answer:

sulfide ion

Explanation:

however, when non-metalic elements gain electrons to form anions the end of their name is change to "-ide".foe example, a flourin atom gains one electronto become a flouride ion(F`) and sulfur gains two electrons to become a sulfide ion(s^2)

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