what is the hydronium ion concentration in a solution formed by combining 750mL of 0.10M NaOH with 250mL of 0.30 M HCl

Answers

Answer 1

Answer:

[tex][H^+]=1x10^{-7}M[/tex]

Explanation:

Hello.

In this case, since the reaction between sodium hydroxide and hydrochloric acid has a 1:1 mole ratio between them:

[tex]NaOH+HCl\rightarrow NaCl+H_2O[/tex]

In order to compute the hydronium H⁺ concentration in the mixed volumes of the given solutions we first compute the moles of each reactant:

[tex]n_{NaOH}=0.750L*0.10mol/L=0.075mol\\\\n_{HCl}=0.250L*0.30mol/L=0.075mol[/tex]

As seen, since those amounts are the same, we infer all the acid and base are consumed so the pH is 7 because a neutral salt is produced, and the corresponding H⁺ concentration is:

[tex][H^+]=10^{-pH}=10^{-7}=1x10^{-7}M[/tex]

Best regards!


Related Questions

How long would it take a bus traveling 52 km/h to travel 130 km

Answers

Answer:

2 and a half hours

Explanation:

Time is equal to distance over speed

A geochemist has determined by measurements that there are moles of tin in a sample of cassiterite. How many moles of oxygen are in the sample

Answers

The question is incomplete, the complete question is:

This is the chemical formula for cassiterite (tin ore): SnO2 A geochemist has determined by measurements that there are 13. moles of tin in a sample of cassiterite. How many moles of oxygen are in the sample? Round your answer to 2 significant digits.

Answer:

Explanation:

In SnO2, there are two moles of oxygen for each mole of tin.

Hence, if there are 13 moles of tin, then we should have 13 * 2 moles of oxygen. This gives us 26 moles of oxygen.

Hence there are 26 moles of oxygen.

9th grade science need help ASAP

Answers

Answer:

D

Explanation:

It is a solid everything that is a solid is heavier

When aqueous solutions of AgNO3 and KI are mixed, AgI precipitates. The balanced net ionic equation is ________. When aqueous solutions of AgNO3 and KI are mixed, AgI precipitates. The balanced net ionic equation is ________. AgNO3 (aq) + KI (aq) → AgI (s) + KNO3 (aq) Ag+ (aq) + I- (aq) → AgI (s) AgNO3 (aq) + KI (aq) → AgI (aq) + KNO3 (s) Ag+ (aq) + NO3 - (aq) → AgNO3 (aq) Ag+ (aq) + NO3 - (aq) → AgNO3 (s)

Answers

Answer:

Ag⁺ (aq) + I¯ (aq) —> AgI (s)

Explanation:

We'll begin by writing the dissociation equation for aqueous AgNO₃ and KI.

Aqueous AgNO₃ and KI will dissociate in solution as follow:

AgNO₃ (aq) —> Ag⁺(aq) + NO₃¯ (aq)

KI (aq) —> K⁺(aq) + I¯(aq)

Aqueous AgNO₃ and KI will react as follow:

AgNO₃ (aq) + KI (aq) —>

Ag⁺(aq) + NO₃¯ (aq) + K⁺ (aq) + I¯(aq) —> AgI (s) + K⁺ (aq) + NO₃¯ (aq)

Cancel out the spectator ions (i.e ions that appears on both sides of the equation) to obtain the net ionic equation. The spectator ions are K⁺ and NO₃¯.

Thus, the net ionic equation is:

Ag⁺ (aq) + I¯ (aq) —> AgI (s)

The net ionic equation of aqueous solutions of [tex]AgNO_3[/tex] and [tex]KI[/tex] to form [tex]AgI[/tex] precipitates is: B. [tex]Ag^{+}_{(aq)} + I^{-}_{(aq)}[/tex] -----> [tex]AgI_{(s)}[/tex]

A balanced chemical equation can be defined as a chemical equation wherein the number of atoms on the reactant (left) side is equal to the number of atoms on the product (right) side.

This ultimately implies that, both the charge on each atom and sum of the masses of the chemical compounds or elements in a chemical equation are properly balanced.

An ion can be defined as an atom or molecules (group of atoms) that has lost or gained one or more of its valence electrons, thereby, making it have a net positive or negative electrical charge.

First of all, we would write the dissociation equation for aqueous solutions of [tex]AgNO_3[/tex] and [tex]KI[/tex]:

For [tex]AgNO_3[/tex]:

[tex]AgNO_3_{(aq)}[/tex] -----> [tex]Ag^{+}_{(aq)} + NO_{3}^{-}_{(aq)}[/tex]

For [tex]KI[/tex]:

[tex]KI_{(aq)}[/tex] -----> [tex]K^{+}_{(aq)} + I^{-}_{(aq)}[/tex]

Next, we would write a chemical equation for the reaction of aqueous solutions of [tex]AgNO_3[/tex] and [tex]KI[/tex]:

[tex]AgNO_3_{(aq)} + KI_{(aq)}[/tex]  -----> [tex]Ag^{+}_{(aq)} + NO_{3}^{-}_{(aq)}[/tex] [tex]+ \;K^{+}_{(aq)} + I^{-}_{(aq)}[/tex] ----->[tex]AgI_{(s)} + K^{+}_{(aq)} + NO_{3}^{-}_{(aq)}[/tex]

Note: Spectator ions refers to the ions that exist as a reactant and a product in a chemical equation because they are unchanged by the chemical reaction.

In this chemical reaction, the spectator ions are:

[tex]K^+[/tex][tex]NO_{3}^{-}[/tex]

Finally, in order to obtain the net ionic equation, we would cancel out the two (2) spectator ions:

[tex]Ag^{+}_{(aq)} + I^{-}_{(aq)}[/tex] -----> [tex]AgI_{(s)}[/tex]

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Many scientists have contributed to the atomic theory. In 1803 John Dalton gave new insight to this theory. Which desciption of an atom fits our most
current understanding?
Fyry nyyden atom is the same as every hydrogen atom

Answers

Im all the help you need if u need to call 813-370-4720

A liquid has rhe following properties : one-phase,colorless,boils it varying temperature. Which of the following BEST describes this liquid
A.Solution
B.substance
C.suspension
D. Coarse mixture

Answers

Answer:

Solution

Explanation:

In science, the solution is a homogeneous mixture of two or more pure substances in proportional concentrations that can be continually varied up to what has been called the solubilization limit. The word solution is usually applicable to the fluid subatomic particle, but gaseous formulations are conceivable.

If you collect 5.74 mL of O 2 at 298 K and 1.00 atm over 60.0 seconds from a reaction solution of 5.08 mL, what is the initial rate of the reaction

Answers

Answer:

7.71 × 10⁻⁴ M/s

Explanation:

The initial rate of the reaction can be expressed by using the formula:

[tex]\dfrac{\Delta [O_2]}{\Delta t}[/tex]

where the number of moles of O₂ = [tex]\dfrac{PV}{RT}[/tex]

where;

Pressue P = 1.00 atm

Volume V =5.74mL =  (5.74 /1000) L

Rate R = 0.082 L atm/mol.K

Temperature = 298 K

[tex]= \dfrac{1.00 \ atm \times \dfrac{5.74 }{1000}L}{0.082 \ L \ atm/mol.K \times 298 K}[/tex]

= 2.35 × 10⁻⁴ mol

Δ[O₂] = [tex]\dfrac{moles \ produced - initial \ mole}{\dfrac{5.08 }{1000}L }[/tex]

Δ[O₂] = [tex]\dfrac{2.35 \times 10^{-4} M - 0 M}{\dfrac{5.08 }{1000}}[/tex]

Δ[O₂]  = 0.04626 M

The initial rate = [tex]\dfrac{\Delta [O_2]}{\Delta t}[/tex]

= [tex]\dfrac{0.04626}{60}[/tex]

= 7.71 × 10⁻⁴ M/s

Three colorless solutions in test tubes, with no labels, are in a test tube rack on the laboratory bench. Lying beside the tests tubes are three labels : 0.10 M Na2CO3, 0.10 M HCL, and 0.10 M KOH. You are to place the labels on the test tubes using only the three solutions present. Here are your tests:
A few drops of the solutions from test tube 1 added to a similar volume of the solution in test tube 2 produces no visible reaction but the solution becomes warm.
A few drops of the solution from test tube 1 added to a similar volume of the solution in test tube 3 produces carbon dioxide gas.
Identify the labels for test tubes 1, 2, and 3

Answers

Answer:

Test tube 1  0.10 M HCL

Test tube 2  0.10 M KOH

Test tube 3 0.10 M Na2CO3

Explanation:

From the question we are told that

    A few drops of the solutions from test tube 1 added to a similar volume of the solution in test tube 2 produces no visible reaction but the solution becomes warm

Generally this warmth is as a result of a reaction between an acid and a base and the acid is 0.10 M HCL and the base is  0.10 M KOH , the heat generated is know as the heat of neutralization,

The reaction is  

       [tex]HCl_{(aq)} + KOH_{(aq)} \rightarrow KCl_{(aq)} + H_2O_{(l)} + \Delta H[/tex]

We are also told from the reaction that

A few drops of the solution from test tube 1 added to a similar volume of the solution in test tube 3 produces carbon dioxide gas.

Generally  carbon dioxide gas  is produced is as a result of  a reaction between the acid HCl  and Na2CO3.

The reaction is

        [tex]2HCl -{(aq)} + Na_2 CO_3_{(aq)} \rightarrow 2 NaCl _{(aq)} + CO_2_{(g)} + H_2O_{(l)}[/tex]

Hence from this explanation above we see that the solution in test tube 1 is  0.10 M HCL while solution in test tube 2 is 0.10 M KOH and then solution in test tube three is  0.10 M Na2CO3

The ion with the smallest diameter is ________. The ion with the smallest diameter is ________. Be2 Sr2 Ca2 Ba2 Mg2

Answers

Answer:

Be2^+

Explanation:

Ionic diameter increases down the group. This implies that Be2^+ will have the smallest diameter.

This extremely small diameter makes Be2^+ to differ considerably from other ions of group 2 elements.

For instance, the compounds of beryllium are mostly covalent in nature.

How much acceleration does a 10 kg object have if pushed by a 75 N force?

Answers

Answer:

a = 7.5 m/s²

Explanation:

Hi there !

Newton's second law

F = m×a => a = F/m

1 N = 1kg·m/s²

a = (75kg.m/s²)/10kg

= 7.5 m/s²

Good luck !

When you finish exercising, you are hot, tired, and sweating. After a bottle of juice, you feel a lot better. Which organ systems are working together in this scenario?

Answers

Answer:

Nervous and Excretory

Explanation:

The nervous system makes you thirsty. The integumentary system makes you sweat. the integumentary system is very similar to the Excretory system.

Nervous and Excretory systems are working together in this scenario.

The nervous system makes you thirsty. The integumentary system makes you sweat. the integumentary system is very similar to the Excretory system.

The blood flow increases, your brain is exposed to more oxygen and nutrients. Exercise also induces the release of beneficial proteins in the brain. Sweating cools the body when it becomes warm. When the body temperature rises, such as when exercising on a hot day, the dermal blood vessels dilate.The excretory system works with the endocrine system to help maintain homeostasis.

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help pls
Which process of sedimentary rock formation occurs last?

cementation
compaction
deposition
erosion

Answers

Erosion is the answer

Answer:

Compaction.

Explanation:

All the others are before this.

Why does sodium chloride form a crystal lattice

Answers

Answer:

Ions of opposite charge strongly attract each other; those of like charges repel. As a result ions in an ionic compound are arranged in a particular manner.

Explanation:

Google is smart

1. In general, what is meant by the term chemical bond? Name and
describe the 3 principle types of chemical bonds.

Answers

Answer: The simplest and most common type is a single bond in which two atoms share two electrons. Other types include the double bond, the triple bond, one- and three-electron bonds, the three-center two-electron bond and three-center four-electron bond. ... Bonds within most organic compounds are described as covalent.

Explanation:

Suppose that Biuret reagent turns purple when it is added to an unknown substance. What can you conclude about the substance?

Answers

Answer:

the unknown substance is a protein

Explanation:

The biuret test is one of the tests for proteins. It  can be used to  detect peptide linkages. The biuret test is carried out in an alkaline solution. A coordination complex is formed  leading to the appearance of a  violet color.

Summarily, the biuret method is a colorimetric technique used to test for proteins and peptides.  It involves the formation of  a purple (violet) complex of Copper salts in alkaline solution.

Hence when the biuret reagent is added to an unknown substance and it turns purple, the unknown substance is a protein

What does reflection mean?

Answers

Answer:

the throwing back by a body or surface of light, heat, or sound without absorbing it.

"the reflection of light"

Explanation:

i hope this helps

Which of the items below is a colloid?
a.fruit salad b.gelatin c.lacquer​

Answers

Answer:

b. gelatin

Explanation:

a homogeneous noncrystalline consisting of large molecules or ultramicroscopic particles of one substance.

pencil has a density of 14.5 g/mL and a volume of 5 mL. Calculate the mass in grams.

Answers

Answer:

The answer is 72.5 g

Explanation:

The mass of a substance when given the density and volume can be found by using the formula

mass = Density × volume

From the question we have

mass = 14.5 × 5

We have the final answer as

72.5 g

Hope this helps you

What two types of elements make up an Ionic bond ?

Answers

Answer:

Metals and Non-metals

Explanation:

Gases A and B are confined to a cylinder and piston and react to form product C. As the reaction occurs, the system loses 1189 J of heat to surroundings. The piston moves downward as the gases react to form a solid. As the volume of the gas decreases under the constant pressure of the atmosphere, the surroundings do 311 J of work on the system. What is the change in the internal energy of the system

Answers

Answer:

The change in the internal energy of the system -878 J

Explanation:

Given;

energy lost by the system due to heat, Q = -1189 J (negative because energy was lost by the system)

Work done on the system, W = -311 J (negative because work was done on the system)

change in internal energy of the system, Δ U = ?

First law of thermodynamics states that the change in internal energy of a system (ΔU) equals the net heat transfer into the system (Q) minus the net work done by the system (W).

ΔU = Q - W

ΔU = -1189 - (-311)

ΔU = -1189 + 311

ΔU = -878 J

Therefore, the change in the internal energy of the system -878 J

2) (3 pts) Convert 85 oF to oC.

Answers

Answer:

The answer will be 29.4˚C.

Explanation:

Using the formula 5(˚F-32)/9, plug in the numbers and you'll get 29.4˚C.

Please help fill in the blanks: The torso, which houses the apparatus consists of upper and lower cavities that are partitioned by the________.The upper cavity is called the _____ (or colloquially the chest) and is almost totally filled with the heart and lungs; the lower the cavity, the abdomen or belly, contains much of the ____ and other organs and glands.

Answers

Answer:

The torso, which houses the apparatus consists of upper and lower cavities that are partitioned by the diaphragm. The upper cavity is called the thoracic cavity (or colloquially the chest) and is almost totally filled with the heart and lungs; the lower the cavity, the abdomen or belly, contains much of the digestive tract and other organs and glands.

Explanation:

The torso, which houses the apparatus consists of upper and lower cavities that are partitioned by the diaphragm. The upper cavity is called the thoracic cavity (or colloquially the chest) and is almost totally filled with the heart and lungs. The thoracic cavity also contains the esophagus, the channel through which food is passed from the throat to the stomach.

The lower the cavity, the abdomen or belly, contains much of the digestive tract and other organs and glands such as the liver, the spleen, the kidneys, as well as the adrenal glands.

Which statements about mixture is FALSE?
A. The ingredients ofvthe mixture keep their physical properties
B. Mixture components can be separated
C. All mixtures are food or drink only
D. A mixture contains more than one ingredients

Answers

It’s b I took the test

A. In a separatory funnel containing ethyl acetate and 10% aqueous sodium bicarbonate (NaHCO3), which layer would contain the brominated aromatic compound?

Answers

Answer:

ethyl acetate layer

Explanation:

This question tests your knowledge of the principle of solvent extraction.

In solvent extraction, there is always an organic layer and an aqueous layer. The ethyl acetate is the organic layer while the sodium bicarbonate is the aqueous layer.

A brominated aromatic compound will be extracted into the organic layer (ethyl acetate layer).


Physical and chemical changes occur all around you every day. Read the story below and use the movable
highlighter pieces to highlight the physical changes in PURPLE and the chemical changes in ORANGE.

Answers

The physical changes are:

"blend up a banana smoothie instead"."cut a piece of bread in half"."I cracked two eggs and whipped them with a fork"."water had evaporated"."glass breaking"."Steam was rolling out"."broke off a piece"."the chocolate melted".

The chemical changes are:

"the milk had soured"."was covered in brown spots"."it was completely tarnished"."plants were dying"."toast must be burning"."rusted bicycle".

Changes of matter

Matter can undergo 2 kinds of changes:

Physical changes: matter changes form but not its identity.Chemical changes: matter changes its identity due to a chemical reaction.

Let's consider the following text.

When my alarm went off at 70'clock, I hit snooze" a few times then finally got out of bed with excitement for my morning bowl of cereal. I poured the cereal and milk into my bowl. But before I even drank it, I could tell from the smell that the milk had soured! So, I decided to blend up a banana smoothie instead. I took some ice out of the freezer and grabbed the only banana that we had in the kitchen, which was covered in brown spots. My grumbling stomach needed to be satisfied before school so I didn't really care.

Just as I was sitting down to drink my smoothie my little brother came bounding into the kitchen and asked, Would you make some eggs and toast for me for breakfast?

"Ugh, sure," I said. I cut a piece of bread in half and put it in the toaster, then I cracked two eggs and whipped them with a fork. I reached for one of my mother's copper cooking pans in the cabinet and saw that it was completely tarnished! I didn't want to be blamed for this, so I ran to tell my mother right away. As I ran out of the kitchen slipped on that banana peel and it smeared all over the floor. As I lay on the floor with the wind knocked from me, I noticed that our family's plants were dying and that some water had evaporated from our fish tank. I made a mental note to take care of these things after school.

Just as I regained my breath and stood up, I heard glass breaking upstairs and my mother shrieking. I ran up the stairs, breathing heavily now. Steam was rolling out from the open bathroom door. When the steam cleared, saw why my mother had been screaming. Before me was my older sister standing in the bathroom with purple hair. I inferred from the scene that my mother had dropped a glass when she first saw her look what your sister did to her hair my mother yelled furiously I decided that I needed to get out of the house immediately, this morning was a crazy one!

A distinct smell was waiting up the stairway and I realized that my brother's toast must be burning! When reached the kitchen, my brother was happily spreading butter on his very browned toast. "I like my toast really crispy!" he said.

"Good I can't handle any more chaos this morning! I exclaimed. I grabbed my backpack headed out into the foggy morning air, and hopped on my slightly rusted bicycle to ride to school. A few minutes into my ride, my stomach grumbled and I realized that I never got a chance to drink my banana smoothie. Luckily, I had stashed a chocolate bar in my backpack yesterday. "Yes! I thought as I stopped pedaling, grabbed the chocolate and broke off a piece. As the chocolate melted in my mouth, I knew that my day was bound to get better!

The physical changes are:

"blend up a banana smoothie instead"."cut a piece of bread in half"."I cracked two eggs and whipped them with a fork"."water had evaporated"."glass breaking"."Steam was rolling out"."broke off a piece"."the chocolate melted".

The chemical changes are:

"the milk had soured"."was covered in brown spots"."it was completely tarnished"."plants were dying"."toast must be burning"."rusted bicycle".

Learn more about physical and chemical changes here: https://brainly.com/question/17384175

4. What reagent would you predict to be in excess for reacting 7.50 mL of a 0.10M BaCl2 solution with 7.50 mL of 0.10M KIO3 solution

Answers

Answer : [tex]BaCl_2[/tex] reagent predict to be in excess.

Explanation : Given,

Concentration of [tex]BaCl_2[/tex] = 0.10 M

Volume of [tex]BaCl_2[/tex] = 7.50 mL = 0.0075 L       (1 L = 1000 mL)

Concentration of [tex]KIO_3[/tex] = 0.10 M

Volume of [tex]KIO_3[/tex] = 7.50 mL = 0.0075 L

First we have to calculate the moles of [tex]BaCl_2[/tex]  and [tex]KIO_3[/tex].

[tex]\text{Moles of }BaCl_2=\text{Concentration of }BaCl_2\times \text{Volume of }BaCl_2[/tex]

[tex]\text{Moles of }BaCl_2=0.10M\times 0.0075L=0.00075mol[/tex]

and,

[tex]\text{Moles of }KIO_3=\text{Concentration of }KIO_3\times \text{Volume of }KIO_3[/tex]

[tex]\text{Moles of }KIO_3=0.10M\times 0.0075L=0.00075mol[/tex]

Now we have to calculate the excess and limiting reagent.

The balanced equilibrium reaction will be:

[tex]BaCl_2+2KIO_3\rightleftharpoons Ba(IO_3)_2+2KCl [/tex]

From the balanced reaction we conclude that

As, 2 mole of [tex]KIO_3[/tex] react with 1 mole of [tex]BaCl_2[/tex]

So, 0.00075 moles of [tex]KIO_3[/tex] react with [tex]\frac{0.00075}{2}=0.000375[/tex] moles of [tex]BaCl_2[/tex]

From this we conclude that, [tex]BaCl_2[/tex] is an excess reagent because the given moles are greater than the required moles and [tex]KIO_3[/tex] is a limiting reagent and it limits the formation of product.

Hence, [tex]BaCl_2[/tex] reagent predict to be in excess.

which material should you use so that the area is cool in terms of temperture O asphalt O red bricks O concrete O soil O

Answers

Answer:

red bricks

Explanation:

right on edg 2020

Red bricks should you use so that the area is cool in terms of temperture. Therefore, option B is correct.

What are red bricks used for?

Red bricks can be used in the construction of structures such as buildings, foundations, arches, pavement, and bridges. These can also be used for aesthetic purposes such as landscaping, face work, and a variety of other architectural purposes.

Traditional red bricks are saw to be more robust, and structures constructed with them are stronger than hollow block structures.Red brick can be warm, with rust or terracotta undertones. They could also be cool and more burgundy.

Thus, Red bricks should you use so that the area is cool in terms of temperture, option B is correct.

To learn more about the red bricks, follow the link;

https://brainly.com/question/14893671

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When 2.16g of H2 reacts with excess O2 by the following equation, 258 kJ of heat are released. What is the change of enthalpy associated with the reaction of 1.00 mol of hydrogen gas? 2H2+O2⟶2H2O

Answers

Answer:

-241 kJ/mol

Explanation:

Let's consider the reaction of hydrogen with excess oxygen to form water.

2 H₂ + O₂ ⟶ 2 H₂O

When 2.16g of hydrogen reacts with excess oxygen, 258 kJ of heat are released, that is, Q = -258 kJ. Considering that the molar mass of hydrogen is 2.02 g/mol, the change of enthalpy associated with the reaction of 1.00 mol of hydrogen gas is:

ΔH° = -258 kJ/2.16 g × (2.02 g/1.00 mol) = -241 kJ/mol

what kind of bonds are there in H2O?​

Answers

Answer: it is covalent and there are 2 hydrogen molecules and 1 oxygen molecule.

Explanation: it just is

In H2O molecule, two water molecules are bonded by a Hydrogen bond but the bond between two H - O bonds within a water molecule are covalent.

Please help I need to turn this in already

Answers

Answer:

The acceleration will be .5 and the force will be 37.5

Have a nice day!   :)

Answer:

Hello. The answer is 37.5N.

Explanation:

If you look carfully ، every time that you add one weight the force changes 2.5N so you can do this:

[tex](2.5 \times 5) + 25 = 37.5[/tex]

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