A student completes a titration by adding 25.0mL of NaOH of unknown concentration to 35.0mL of 0.25M HCl. What is the molar concentration of NaOH? If it takes 15 mL of 0.5M sodium hydroxide solution to neutralize 200 mL of Hydrochloric acid, what is the concentration of HCl? THIS IS TIMED PLEASE HELP! (include work shown)

Answers

Answer 1

Answer:

0.35M NaOH and 0.0375M HCl.

Explanation:

NaOH reacts with HCl as follows:

NaOH + HCl → NaCl + H2O

Where 1 mole of NaOH reacts per mole of HCl

To solve the first question we must find the moles of HCl that reacted = Moles NaOH in the unknown. With the moles and the volume we can find its molar concentration:

Moles HCl = Moles NaOH:

0.0350L * (0.25mol / L) = 0.00875 moles NaOH

In 25.0mL = 0.0250L:

0.00875 moles NaOH / 0.0250L =

0.35M NaOH

For the second question, the moles of NaOH = moles HCl. With the 200mL = 0.200L the molarity is:

Moles NaOH = Moles HCl:

0.015L * (0.5mol / L) = 0.0075 moles HCl / 0.200L =

0.0375M HCl


Related Questions

Research online to find out what the acidity of the rainfall is where you live. If you live in an area which is affected by acid rain, where do you think it is coming from and why?
Write 3-5 paragraphs describing the effects.
If you do not live an area effected by acid rain, choose another city that is effected by acid rain.

Answers

Answer & Explanation: Acid rain occurs when sulfur dioxide and nitrogen oxide are released into the air to create a chemical reaction. When the two mix in the air (oxygen), they will get into the water and mix with other pollutants in the air, making acid rain.

Answer:

   What is acid rain? Acid rain occurs when sulfur dioxide and nitrogen oxide are released into the air to create a chemical reaction. When the two mix in the air (oxygen), they will get into the water and mix with other pollutants in the air, making acid rain.

   What causes acid rain the most? It can be caused by useing nonrenewable resources. Which inclues coal, oil, ect.

   What effects can acid rain have? It causes respiratory issues in animals and humans. When acid rain falls down and flows into the rivers and ponds it affects the aquatic ecosystem. It alters the chemical composition of the water, to a form which is actually harmful to the aquatic ecosystem to survive and causes water pollution  which can harm our fresh water supply.

How many moles of Ca(OH)2 are needed to make 200.0 mL of 0.250 M solution? Ca(OH)2

Answers

Answer:

0.05 moles of Ca(OH)2

Explanation:

The formula for molarity is: mol/L = M

First, convert 200.0 mL to L.

200 mL/1000 = 0.2 L

Next, plug in the values given.

mol/0.2 = 0.250

Rearrange the equation.

mol = 0.2*0.250

mol = 0.05

If you'd like to check it, simply plug in 0.05 to mol and divide it by 0.2. In theory, you should get 0.250.

DIRECTIONS: Classify the following unbalanced chemical equations according to the six types
of chemical reactions. Write your answer on the space provided for each number.
1. NaOH + KNO3 NaNO3 + KOH
2. CH4 + O2 CO2 + 2H2O
3. Fe + NaBr FeBr3 + Na
4. CaSO4 + Mg(OH)2 Ca(OH)2 + MgSO4
5. NH4OH + HBr H2O + NH4Br
6. P4 + O2 P2O4
7. NaNO3 NaNO2 + O2
8. C18H18 + O2 CO2 + H2O
9. H2SO4 + NaOH NaSO4 +H2O
10.NiSO4 + Li3PO4 Ni3(PO4)2 + Li2SO4

Answers

1. Double replacement
2. Combustion
3. Single replacement
4. Double replacement
5. Double replacement
6. Synthesis
7. Decomposition
8. Combustion
9. Double replacement
10. Double replacement

Also you can use webqc.org/balance.php to balance them. Its a free website and it tells you what type of reaction and the coefficients

They have one electron in the outermost electron shell. These are very active metals and easily lose their single valence electron.

Answers

Answer: The statement they have one electron in the outermost electron shell. These are very active metals and easily lose their single valence electron, is true.

Explanation:

Metals are the species which tend to lose electron(s) to acquire stable noble gas configuration.

Elements which tend to lose a single electron in order to acquire stability are active in nature because losing one electron is more easy as compared to losing two or more electrons.

For example, atomic number of sodium is 11 and its electronic distribution is 2, 8, 1.

Since, it contains only one valence electron and by losing it sodium will acquire stability. Hence, sodium is a very reactive metal.

Thus, we can conclude that the statement they have one electron in the outermost electron shell. These are very active metals and easily lose their single valence electron, is true.

Balance :FeCl3 + __Ca(OH)2 → ___ Fe(OH)3 + __ CaCl2

Answers

Your answer is 2:3:2:3

Reaction B: 2 H2O2 (aq) + 2 H20 (L) + O2 (g)
10. Identify the reactants in Reaction B.
11. Identify the products in Reaction B.
12. How many molecules are present on the reactant side of the equation?
13. How many molecules are present on the product side of the equation?

Answers

Answer: 10. The reactant in Reaction B is [tex]H_{2}O_{2}[/tex].

11. The products in Reaction B are [tex]H_{2}O[/tex] and [tex]O_{2}[/tex].

12. There are 2 molecules present on the reactant side of the equation.

13. There are 3 molecules present on the product side of the equation.

Explanation:

The given reaction equation is as follows.

[tex]Reaction B: 2H_{2}O_{2}(aq) \rightarrow 2H_{2}O(l) + O_{2}(g)[/tex]

Reactants are the species present on the left side of a chemical equation.

Products are the species present on the right side of a chemical equation.

Therefore, the reactant in Reaction B is [tex]H_{2}O_{2}[/tex]. As 2 is coefficient of [tex]H_{2}O_{2}[/tex] so, 2 molecules are present on the reactant side of the equation.

The the products in Reaction B are [tex]H_{2}O[/tex] and [tex]O_{2}[/tex]. The coefficient of [tex]H_{2}O[/tex] is 2 and coefficient of [tex]O_{2}[/tex] is 1. Hence, there are total (2 + 1) equals to 3 molecules present on the product side of the equation.

Thus, we can conclude that:

The reactant in Reaction B is [tex]H_{2}O_{2}[/tex].

The products in Reaction B are [tex]H_{2}O[/tex] and [tex]O_{2}[/tex].

There are 2 molecules present on the reactant side of the equation.

There are 3 molecules present on the product side of the equation.

Mrs. Borunda has a sample of oxygen gas that occupies a volume of 600 L at 400 atm pressure. What will the pressure be if she increases the volume to

800 L?

300 atm

450 atm

540 atm

250 atm

Answers

Answer:

P₂ = 300 atm

Explanation:

Given that,

Initial volume, V₁ = 600 L

Initial pressure, P₁ = 400 atm

We need to find the pressure if the volume is 800 L.

We know that the relation between pressure and volume is given by :

[tex]P\propto \dfrac{1}{V}\\\\\dfrac{P_1}{P_2}=\dfrac{V_2}{V_1}\\\\P_2=\dfrac{P_1V_1}{V_2}\\\\P_2=\dfrac{600\times 400}{800}\\\\P_2=300\ atm[/tex]

So, the new pressure is equal to 300 atm.

Why are humans responsible for oil spills

Answers

Answer:

Oil spills into rivers, bays, and the ocean most often are caused by accidents involving tankers, barges, pipelines, refineries, drilling rigs, and storage facilities.

Spills can be caused by:

people making mistakes or being careless.

equipment breaking down.

natural disasters such as hurricanes.

deliberate acts by terrorists, countries at war, vandals, or illegal dumpers.

Explanation:

Hope this helped Mark BRAINLIEST!!!

The table below shows the height of a ball x seconds after being kicked.

A 2-column table with 5 rows. The first column is labeled time (seconds) with entries 0, 0.5, 1, 1.5, 2, 2.5, 3. The second column is labeled height (feet) with entries 0, 35, 65, 85, 95, 100, 95.
What values, rounded to the nearest whole number, complete the quadratic regression equation that models the data?

f(x) =
x2 +
x + 0
Based on the regression equation and rounded to the nearest whole number, what is the estimated height after 0.25 seconds?

feet

Answers

Answer:

-16

81

19

Explanation:

The quadratic regression equation is [tex]y = -16x^2 +81x[/tex], and the estimated height in 0.25 seconds is 19 feet

What are regression equations?

Regression equations are used to determine the relationship between sets of data

The dataset is given as:

Time (seconds)       Height (feet)

       0                               0

      0.5                            35

         1                              65

        1.5                             85

         2                              95

        2.5                           100

           3                             95

To determine the quadratic regression equation, we make use of a graphing calculator.

From the graphing calculator, we have the following calculation summary:

a = -16.429

b = 81.071

c = -0.357

A quadratic regression equation, is represented as:

[tex]y = ax^2 + bx + c[/tex]

So, we have:

[tex]y = -16.429x^2 +81.071x -0.357[/tex]

Approximate

[tex]y = -16x^2 +81x[/tex]

The estimated height in 0.25 seconds is:

[tex]y = -16* 0.25^2 +81 * 0.25[/tex]

[tex]y = 19.25\\[/tex]

Approximate

[tex]y = 19[/tex]

Hence, the estimated height in 0.25 seconds is 19 feet

Read more about quadratic regression at:

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What does temperature surround when the kinetic energy is moving fast ?

Answers

When the average kinetic energy of its particles increases, the object's thermal energy increases. Therefore, the thermal energy of an object increases as its temperature increases.

In chemistry, we define the temperature of a substance as the average kinetic energy of all the atoms or molecules of that substance. Not all of the particles of a substance have the same kinetic energy. At any given time, the kinetic energy of the particles can be represented by a distribution.

In physics, temperature is defined as the average kinetic energy of the particles in an object. ... When particles move more quickly, temperature is higher and an object feels warmer. When particles move more slowly, temperature is lower and an object feels cooler.

乁(ᵔヮᵔ)ㄏ

How does velocity affect the movement of an object?

Answers

the higher the velocity the faster it moves

Answer:

when the velocity is at a higher *rate of speed*, the faster the object will move!

Explanation:

Many electrical power plants use fossil fuels, a non-renewable resource to produce electricity?

A:Solar energy can be used to push energy along power lines

B:Wind energy can be used to cool overheated electrical lines

C:Moving water can be used to carry electricity to homes and businesses

D:Biomass can be used to generate heat that can be converted into electricity

Answers

Answer:

Explanation:

Thermal Power Plants generate electricity by converting heat into electricity, essentially by burning a fuel. ... A coal power plant works in much the same way, but instead of a nuclear reactor heating water to make steam, the heat from the burning coal powers a steam turbine

Answer:

 

Solar energy can be used to push energy along power lines.

Explanation:

Im Might be wrong, might have to fact check it but im taking the test now so :)

All of the following are empirical formulas except:

C2H3O2


C6H6

CHO2

CH2O

Answers

The answer to this question is B; C6H6 is not an empirical formula as it can continue to be reduced to CH

e) A plutonium atom splits apart to form two smaller atoms and free neutrons,
What type of reaction is this, where is it most likely to occur, and what else is
emitted during the reaction? (3 points)

Answers

Answer:

subject?

Explanation:

What molar concentration (molarity) results when 1.28 L of 14.38 M HCl is diluted to 9.45 L of water?

Answers

Answer:

1.95 M

Explanation:

Molarity is a measure of the molar concentration of a substance (solution). In relation to the volume, it is calculated using the formula as follows;

C1V1 = C2V2

Where;

C1 = initial concentration (M)

C2 = final concentration (M)

V1 = initial volume (L)

V2 = final volume (L)

According to the provided information in this question;

C1 = 14.38 M

C2 = ?

V1 = 1.28 L

V2 = 9.45 L

Using C1V1 = C2V2

14.38 × 1.28 = C2 × 9.45

18.4064 = 9.45 C2

C2 = 18.4064 ÷ 9.45

C2= 1.95 M

2. Identify the limiting reactant when 4.68 g of iron reacts with 2.88 g of sulfur to produce Fes.
Fe +
_Sg → FeS
B
C с
A
+


Help please I’ll mark brainliest

Answers

Answer:

Iron is limiting reactant

Explanation:

Based on the reaction:

Fe + S → FeS

1 mole of iron reacts per mole of Sulfur

To solve this question we must convert the mass of each reactant to moles using molar masses of each reactant. As the reaction is 1:1, the reactant with the lower amount of moles is limiting reactant.

Moles Fe -Molar mass: 55.845g/mol-

4.68g * (1mol / 55.845g) = 0.0838 moles

Moles S -Molar mass: 32.065g/mol-

2.88g * (1mol / 32.065g) = 0.0898 moles

As the amount of moles of Fe < Moles S,

Iron is limiting reactant

When 4.68 g of iron reacts with 2.88 g of sulfur to produce FeS, iron is the limiting reagent.

What is limiting reagent?

If in a chemical reaction two reactants are present and one of them is present in less quantity as compared to other, is known as limiting reagent.

Given chemical reaction is:
Fe + S → FeS

From the stoichiometry of the reaction it is clear that equal moles of both reactant is required for the formation of product, so their mole ratio is 1:1.

Now we calculate the moles by using the formula:

n = W/M, where

W = given mass

M = molar mass

Moles of 4.68g of iron = 4.68g / 55.845g/mole = 0.0838 moles

Moles of 2.88 of sulfur = 2.88g / 32.065g/mole = 0.0898 moles

Moles of iron is less as compare to the sulfur, so it is the limiting reagent.

Hence, iron is the limiting reagent.

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.?lkikjjjmmjj
hhhhgyhhjjj

Answers

Answer:

ertyuioekgdctifrofy?

Explanation:

The decomposition of potassium chlorate, KClO3, is used as a source of oxygen in labs.
How many moles of potassium chlorate are needed to produce 6.83 moles of oxygen gas?

Answers

Reaction takes place is

2KClO3 --> 2KCl + 3O2

from above equation 2 moles of potassium chlorate is forming 3 moles of Oxygen gas.

now given 6.83 moles of oxygen and moles of potassium chlorate is missing,

consider x moles of potassium chlorate are needed to form 6.83 moles of oxygen

from above condition, .

3 》》》》2

x 》》》》6.83

3/x = 2/6.83

x = 3×6.83/2

x= 10.245

Answer- 10.245 moles of potassium chlorate are needed to produce 6.83 moles of oxygen gas.

Proponer una propuesta de acción contra la degradación del suelo basándose en tres tipos de argumentos de fuentes confiables

Answers

Answer:

Cobertura vegetal, mantillo y piedra triturada.

Explicación:

Para evitar la degradación del suelo, debemos plantar una cubierta vegetal perenne que proteja el suelo de la erosión del viento y el agua sujetándolo firmemente con sus raíces. El mantillo también se usa para prevenir la erosión del suelo. En aquellas zonas donde la cobertura vegetal no es posible, tenemos que utilizar piedras trituradas para cubrir el suelo con el fin de evitar el contacto directo con el viento. Entonces, estas acciones pueden prevenir la degradación del suelo y mantener el suelo en su estado original.

What is the correct unit for M1 and M2?

Answers

Answer:

M1 and M2 are the masses of two. objects exerting the force on each other, and R is the distance. between their centers.

Explanation:

M1 and M2 are the masses of two. objects exerting the force on each other, and R is the distance. between their centers.

(part 1 of 3) Copper reacts with silver nitrate through a single replacement. If 1.29 g of silver are produced from the reaction, how much copper(II) nitrate is also produced? Answer in units of mol. (part 2 of 3) How much Cu is required in this reaction? Answer in units of mol. (part 3 of 3) 1.0 points How much AgNO3 is required in this reaction? Answer in units of mol.

Answers

Answer:

See explanation.

Explanation:

Hello there!

In this case, according to the described chemical reaction, we first write the corresponding equation to obtain:

[tex]Cu+2AgNO_3\rightarrow 2Ag+Cu(NO_3)_2[/tex]

Thus, we proceed as follows:

Part 1 of 3: here, since the molar mass of silver and copper (II) nitrate are 107.87 and 187.55 g/mol respectively, and the mole ratio of the former to the latter is 2:1, we can set up the following stoichiometric expression:

[tex]m_{Cu(NO_3)_2}=1.29gAg*\frac{1molAg}{107.87gAg}*\frac{1molCu(NO_3)_2}{2molAg}*\frac{187.55gCu(NO_3)_2}{1molCu(NO_3)_2} \\\\m_{Cu(NO_3)_2}=1.12gCu(NO_3)_2[/tex]

Part 2 of 3: here, the molar mass of copper is 63.55 g/mol and the mole ratio of silver to copper is 2:1, the mass of the former that was used to start the reaction was:

[tex]m_{Cu}=1.29gAg*\frac{1molAg}{107.87gAg}*\frac{1molCu}{2molAg}*\frac{63.55gCu)_2}{1molCu} \\\\m_{Cu}=0.380gCu[/tex]

Part 3 of 3: here, the molar mass of silver nitrate is 169.87 g/mol and their mole ratio 2:2, thus, the mass of initial silver nitrate is:

[tex]m_{AgNO_3}=1.29gAg*\frac{1molAg}{107.87gAg}*\frac{2molAgNO_3}{2molAg}*\frac{169.87gAgNO_3}{1molAgNO_3} \\\\m_{AgNO_3}=2.03gAgNO_3[/tex]

Best regards!

On the following chemical equation, label the acid, the base, the
conjugate acid, and the conjugate base.
HX(aq) + H2O(1) = H30+(aq) + X (aq)

Answers

Answer:

HX (aq)    +     H₂O (l)  ⇄      H₃O⁺ (aq)    +     X⁻ (aq)  

Acid                  Base          Conj. acid          Conj. base  

Explanation:

The equation is:

HX (aq) + H₂O (l)  ⇄   H₃O⁺ (aq) + X⁻ (aq)

This is the typical equilibrium for a weak acid. It would complete if we notice the Ka.

HX (aq) + H₂O (l)  ⇄   H₃O⁺ (aq) + X⁻ (aq)    Ka

1 mol of hypothetic HX acid react to 1 mol of water in order to release a proton and make hydronium and generate the X⁻ anion.

HX will be the acid, in this case a weak one and water will be the base. Water is able to accept a proton to make itslef hydronium

Hydronium is the conjugate acid.

The X⁻ will be the conjugate strong base.

This ion can generate the acid form again, that's why it is strong, because it can make hydrolisis.

X⁻ (aq)  +  H₂O (l)  ⇄  HX (aq) +  OH⁻(aq)     Kb

In this case, the anion will be the conjugate base which it takes a proton from water (acid form) to make a conjugate acid, the HX and a conjugate base, OH⁻

When writing the formulas for a compound that contains a polyatomic ion, ... ?​

Answers

Answer:

The cation is written first in the name; the anion is written second in the name. Rule 2. When the formula unit contains two or more of the same polyatomic ion, that ion is written in parentheses with the subscript written outside the parentheses.

When writing the formula of a compound that contains polyatomic ion, the metal is written first followed by the central atom in the ion and then other atoms that surround the central atom.

A poly atomic ion refers to an ion that comprises of more than one atom. Such ions are common in chemistry. Examples of polyatomic ions include; PO4^3-, BH4^- etc.

When writing the formula of a compound that contains a polyatomic ion, the metal is written first then the central atom in the ion follows before other atoms that surround the central atom in the ion.

Learn more: https://brainly.com/question/6284546

PLEASE HELP!
an element with 8 protons and 10 neutrons

Answers

Answer:

oxygen ion O2-

Explanation:

because it has 8 protons and gave gained 2 electron so O2-.

CH3OH is an example of a ____ hydrocarbon.
a.
complete
b.
substituted
c.
functional
d.
synthetic

Answers

Answer:

functional

Explanation:

c is correct

3. How much heat (in joules) is needed to raise the temperature of 355 g of ethanol I

(c = 2.4 J/gºC) by 63°C?

q=mcAT

Answers

Answer:

53676 J

Explanation:

m = 355 g

c = 2.4 J/gºC

ΔT = 63°C

q = mcΔT

  = (355)(2.4)(63)

  = 53676 J

The amount of heat is 53676J to raise the temperature of 355 g of ethanol.

What is temperature?

Temperature is a measurement of the amount of energy of the atoms in a system or a physical quantity that expresses hot and cold.

What is heat?

Heat is energy that is transmitted through one body to some other due to a temperature differential. When two bodies of different temperatures come together, energy can be transferred (heat flows) from the hotter to the colder.

It can be determined by the formula:

q =mCΔT.

where, q is heat, m is mass , C is and T is temperature.

Calculation of heat is shown below:

It is given that, mass of ethanol = 355 g, c = [tex]2.4 J/g^{0}[/tex] C, ΔT. = [tex]63^{0} C[/tex]

Now, put the values of given data in heat formula:

q =mCΔT

= 355×2.4×63

=53676J.

Therefore, the amount of heat will be 53676J to raise the temperature of 355 g of ethanol

To know more about heat and temperature click here.

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Drag each tile to the correct box,
Arrange the processes of the water cycle in the correct order, starting with the heat from the Sun.

Answers

Number one sun, then rain, then evaporate then it starts over

Answer:

4

3

2

6

1

5

I hope this helped!

Which results in a chemical change?

A. A teacher feels a rough cloth

B. A student colors a blue paper

C. A student smells a flower

D. A teacher lights a candle

Answers

Answer:

D. I am pretty sure

Explanation:

:))))))

Answer:

D. A teacher lights a candle

Explanation:

Help asap plzzzz 30 points
A chemistry teacher provides students with the amount of potassium hydroxide they need in solution form. The teacher makes the solution by dissolving 42.1 g KOH into 3.0 L of solution.


Each lab group needs 0.023 mol of KOH for their experiment. How many milliliters of the solution does each group need to provide enough dissolved moles?

mL of solution

Answers

Answer:

Do you need your 0.00 2 oz

Explanation:

Because that is the right answer

For the enough dissolving of given moles each group will need to provide 92mL of solution.

How we determine Molarity for further calculation?

Molarity can be calculated as: M = n/V mol/L where,

V = volume = 3L (given)

n = no. of moles, which can be calculated as:

n = W/M, where

W = given mass = 42.1g (given)

M = molar mass = 56.1g/mol (known)

First of all we have to calculate molarity to determine the volume of solution of each groups. By putting value of n in the 1st equation, molarity can be calculated as follow:

M = 42.1 / 56.1 × 3 = 0.250 mol/L

Now in the question it is given that each group have KOH solution of 0.023 moles. So, we can calculate the volume by using the 1st equation:

M = n/V

0.250 = 0.023/V

V = 0.023mol / 0.250mol per L = 0.092L = 92mL.

Hence, 92mL of the solution will each group need to provide enough dissolved moles

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Please help!!

All fake answers get reported immediately. Yes, I am a girl -_-

Answers

Answer:

1.)C₃H₈O

2)OH

3.)1-propanol

1.) C4H8O

2.) C2H6O or CH3CH2OH

3.)Ethanol

Explanation:

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