Which aqueous solution is expected to have a pH less than 7 at 25∘C?
a) LiNO3 (aq)
b) NH4Br (aq)
c) RbC2H3O2 (aq)
d) MgCl2 (aq)

Answers

Answer 1

[tex]NH_{4} Br[/tex](aq ) is expected to have a Ph less than 7 as on dissociation the following constituents will separate

[tex]NH_{4} Br[/tex]    +  [tex]H_{2}O[/tex]    → [tex]NH_{4} OH[/tex](weak base)    +   [tex]HBr[/tex] (strong acid)

A weak base is a strong acid hence B is  correct

[tex]LiNO_{3}[/tex] It is a salt of a strong base and weak acid hence basic  and a PH greater than 7

[tex]MgCl_{2}[/tex]it is a salt of a strong base and strong acid hence a neutral solution of PH 7

[tex]RbCH_{2} H_{3} O_{2}[/tex] It is a salt of a strong base and weak acid hence basic  and a PH greater than 7

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Related Questions

Which equation obeys the law of conservation of mass? h2(g) o2(g) → h2o(g) h2(g) o2(g) → h2o(g) 4he(g) 2h2(g) o2(g) → 2h2o(g) h2(g) → h2o(g) h2(g) o2(g) → 2h2o(g)

Answers

2H(g) + [tex]O_{2}[/tex] ⇒ 2H2O This equation obeys the law of conservation of mass.

The law of conservation of mass states that mass is neither created nor destroyed in chemical reactions. For example, carbon atoms in coal become carbon dioxide when burned. A carbon atom changes from a solid structure to a gas, but its mass remains the same.

In a chemical reaction, the mass of the chemical components before the reaction equals the mass of the components after the reaction. Therefore, for chemical reactions and low-energy thermodynamic processes in isolated systems, the total mass of reactants or starting materials must equal the mass of the products.

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Help me with this question please.​

Answers

Explanation:

conduction because it has succession

Express the composition of each compound as the
mass percent of its elements (percent composition).
a.
sucrose (C,H),0.,)
c. magnetite (Fe,O.)
b.
aluminum sulfate
(Al, (SO,).)

Answers

The composition of each compound as the mass percent of its elements is as follows:

For Sucrose - Carbon is 42.18%, Hydrogen is 6.44% and Oxygen is 51.38%.For Aluminum sulfate - Aluminum is 3.99%, Sulfur is 4.57% and Oxygen is 87.44%.For Magnetite - Iron is 71.83% and Oxygen is 28.17%.What is mass percent?

Concentration is expressed as mass percent. Additionally, the ingredients in a particular mixture are described. Solution composition can be understood in terms of mass percent. It indicates the mass of solute present in a solution of a given mass. The amount of solute is expressed in mass or moles.

Mass Percent = (Component Mass ÷ Total Mass) x 100% or

(mass of solute ÷ mass of solution) x 100%

a. Sucrose (C₁₂H₂₂O₁₁) with molecular mass of 342.296 u composed of:

Carbon: (12 x 12.01) / 342.296 = 42.18%

Hydrogen: (22 x 1.01) / 342.296 = 6.44%

Oxygen: (11 x 16) / 342.296 = 51.38%

b. Aluminum sulfate (Al₂(SO₄)₃) with molecular mass of 342.14 u is composed of:

Aluminum: (2 x 26.98) / 342.14 = 3.99%

Sulfur: (3 x 32.06) / 342.14 = 4.57%

Oxygen: (18 x 16) / 342.14 = 87.44%

c. Magnetite (Fe₃O₄) with molecular mass of 231.534 u is composed of:

Iron: (3 x 55.85) / 231.534 = 71.83%

Oxygen: (4 x 16) / 231.534 = 28.17%

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Your body is made up of trillions of cells that perform all the functions you need to survive. Which other kinds of organisms are composed of cells?

Only animals are composed of cells.
Only animals are composed of cells.

Only animals and plants are composed of cells.
Only animals and plants are composed of cells.

Only animals, plants, and bacteria are composed of cells.
Only animals, plants, and bacteria are composed of cells.

All organisms are composed of cells.

Answers

All organisms are composed of cells.

If 33.0 grams of hydrogen gas react with 300. grams of oxygen gas, what is the percent yield if an experiment produces 250. grams of water? Use the balanced equation from question 3.

Answers

Answer:

can you show us question 3 pls

Explanation:

When students work in a chemistry lab, the location of which item would be the most important for each student to know?
A.broom and dust pan, in case the student needs to sweep up broken glass

B.baking soda, in case the student needs to neutralize an acid spill

C.ice maker, in case the student needs to cool off hot glassware

D.safety shower, in case a chemical is spilled on the student’s body

Answers

Answer:

answer is D. safety shower, in case a chemical is spilled on the student’s body on edge 2020

Explanation:

have a great day peeps :)

It is important for student's to know the location of safety shower, in case a chemical is spilled on the student’s body which can be avoided by wearing proper personal protective equipments.

What are personal protective equipments?

Personal protective equipment is a protective clothing which is worn to protect the wearer's body from hazard or injury.The hazards which can be addressed by the use of personal protective equipment are physical,chemical and bio hazards.

It imposes a barrier between the user and the working environment.The main purpose of personal protective equipment is to reduce exposure of employees to the hazards.

It has a limitation that it does not eliminate the hazard and may lead to harm to the employee if the equipment is damaged.

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Potassium Permanganate is used for purifying drinking water, because

A. it is a sterilising agent
B. it dissolves the impurities of water
C. it is a reducing agent
D. it is an oxidising agent

Answers

Answer:

D. it is an oxidizing agent

Explanation:

plz draw a periodic table with all its information​

Answers

Answer:

Explanation:

Hope this helps u!!

Answer:

plz following me ❤❤...........,...,.,.

Look at the general chemical equation below. A B C Which situation best describes the effect of a limiting reactant

Answers

The situation that best describes the effect of a limiting reactant is that when there is not enough A reactant to react with whole B.

The limiting reactant, also known as the limiting reagent, is the reactant that is used first during a chemical reaction, hence restricting the amount of product that can be produced. The limiting reactant can be identified in a variety of methods ,but they all require employing mole ratios from the balanced chemical equation.

The theoretical yield is the maximum quantity of product possible given the limiting reactant. The quantity of product actually procured, or actual yield, is usually always less than the theoretical yield. The percentage yield used to describe the actual yield indicates what portion of the theoretical yield was attained.

In the equation there is only one situation which describes the effect of limiting reagent when there is not enough of A to react with whole B.

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An element is reduced while another element is oxidized. 1. Acid base 2. Redox 3. Precipitation 4. Combustion

Answers

[tex] \huge\hookrightarrow \mathtt{ Answer }[/tex]

The reaction in which one element is oxidized and other element is reduced is known as :

[tex] \huge \boxed{ \mathbb{redox}}[/tex]

Answer:

[tex]\huge \mathcal{Answer}࿐Answer࿐[/tex]

[tex]\huge \mathcal{ redox} \:[/tex]

I hope it helps

have a nice day

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The_____gene shows up even when inherited only from one parent.

Answers

Answer:

The Alleles gene shows up even when inherited only from one parent

Explanation:

The two alleles in a gene pair are inherited, one from each parent. Alleles interact with each other in different ways. These are called inheritance patterns.

i hope this helped

Determine 4.86×10^24 atoms Au to grams

Answers

The mass of 4.86 × 10²⁴ Au atoms is equal to  1589.6 g.

What is Avogadro's number?

Avogadro’s number can be used to express the number of entities such as molecules, atoms, ions, electrons, or protons in one mole of any substance.

The value of Avogadro’s constant is equal to 6.022 × 10²³ per mole.

Given, the number of atoms of the Au =  4.86 × 10²⁴

The atomic mass of the Au = 197 g/mol

So 6.022 × 10²³ atoms of Au have mass = 197 g

Then 4.86 × 10²⁴ Au atoms will have mass =  1589.6 g

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Write the chemical symbols for three different atoms or atomic anions with 10 electrons

Answers

Answer:

          i)  Neon (Ne)

           ii)  Fluoride Ion (F⁻¹)

            iii)  Oxide Ion  (O⁻²)

Explanation:

                  Ions are those charged species which are either positively charged (by loosing electrons) called as cations or negatively charged (by gaining electrons) called as anions.

                 In given examples, Neon is a neutral atom which has an atomic number 10. It contains 10 electrons in its neutral state with the electronic configuration 1s², 2s², 2p⁶.

                 Fluorine atom has an atomic number of 9. Therefore, it contains 9 electrons in its neutral state with an electronic configuration of 1s², 2s², 2p⁵. When Fluorine atom gains one electron it gets 10 electrons with electronic configuration of 1s², 2s², 2p⁶.

                Oxygen atom has an atomic number of 8. Therefore, it contains 8 electrons in its neutral state with an electronic configuration of 1s², 2s², 2p⁴. When Oxygen atom gains two electron it gets 10 electrons with electronic configuration of 1s², 2s², 2p⁶ forming an Oxide Ion.

Safety standards require a pool to add 333 chlorine tablets to every 2{,}0002,0002, comma, 000 liters of water. Today, the lifeguards at Park Pool added 888 chlorine tablets to their pool's 10{,}00010,00010, comma, 000 liters of water. How does Park Pool's chlorine compare to the safety standards

Answers

Compared to safety standards, that would be too little chlorine:

10,000 gallons is five times as much water as 2,000.

Therefore, Park's pool needs five times as much chlorine as is required for 2,000 gallons to meet safety regulations.

5 times 3 pills of chlorine equals 15 tablets. For Mark to meet safety standards, 15 chlorine tablets would be required. Use one three-inch tablet for every 10,000 gallons of pool water rather than stuffing your chlorinator or floater to the brim with tablets. This quantity of pills should be sufficient to maintain a good chlorine level if you shock your water once a week.

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A sample of gas has a pressure of 3.4 atm at 300 K in a container with a fixed volume. What will be the pressure (in atm) of this same sample of gas if the temperature is changed to 402 K

Answers

If the temperature is raised to 402 K, the pressure (in atm) of this given sample of gas will be 4.5.

Given,

Pressure P1 = 3.4 atm

Temperature T1 = 300 K

       ⇒            T2 = 402 K

   ⇒                P2 = ?

    ⇒          P1/T1 = P2/T2

 ⇒         3.4/300 = P2/402

    ⇒              P2 = 4.5

   ⇒     Pressure = 4.5 atm

An atmosphere (atm) is a measuring unit that corresponds to the average air sea level pressure at 15 degrees Celsius (59 degrees Fahrenheit). One atmosphere consists of 1,013 millibars of pressure, or 760 millimetres (29.92 inches) of mercury.

Pressure is defined as the force exerted by one material on another per unit area. The force also that gas exerts on the container limits is defined as gas pressure. Gas molecules travel at random over the specified volume. They clash with the surface as well as each other during this movement.

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draw a diagram of the structure of the following atoms and state their electron arrangement:

(i) Mg
(ii)Ca

Answers

The diagrams of the arrangement of the electrons in calcium and magnesium have been shown in the image attached to this answer. There are two electrons in the valence shell of calcium.

How are the electrons arranged?

We know that the electrons are the subatomic particles that we can be able to see in the shells of the atom. It is important that we ought to know that the electrons are the particles that are known to be responsible for the reactivity of the atom.

The number of the electrons that we can find in the atom would depend on the number of the protons that we have in the nucleus of the atom and this is because for the atom to be electrically neutral then we would have to have the same number of electrons and protons being in the atom as we know.

It is clear that calcium is a member of group two of the periodic table and that magnesium is also a member of group two of the periodic table.

The structures for calcium would have Ca and two dots while that of magnesium would have Mg and two dots.

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6. Which subatomic particle has no charge?
O proton
O electron
O neutron

Answers

Answer:

O Neutron

Explanation:

Answer:

the anwser is

electron

HOPE IT HELPED

The first substance is nitric acid, HNO3. Since this substance dissolves to generate an acidic solution, the bond between O and H in the structural formula NO2OH breaks when the substance dissolves, making it an oxyacid. The latter substance, Ni(OH)2, is apparently insoluble in neutral water, but will dissolve if the solution is acidic. This behavior is typical of substances that feature basic anions. The bond between Ni and O is the one that breaks when Ni(OH)2 dissolves. The hydroxide ion that is produced quickly reacts with protons in solution and cannot react again with Ni2 to form a precipitate.

Answers

Ni(OH)₂ is base but this is not strong base this is very weak base and this cannot gives OH⁻ after dissolving in H₂​​​O . this is only dissolve in acidic solution.

Define acidic solution.

A solution is said to be acidic if it contains more positively charged hydrogen ions (H⁺) than negatively charged hydroxide ions (OH⁻). Lemon juice and vinegar are typical examples of acids. The amount of OH ions is greater in bases. Baking soda and regular ammonia are common examples.

Acidic substances can typically be distinguished by their sour flavor. A basic definition of an acid is a molecule that can donate an H⁺ ion and can continue to be energetically favorable even after losing H⁺. Blue litmus paper has a reputation for turning red when exposed to acids. Bases, on the other hand, are distinguished by their bitter flavor and slick consistency.

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You want to sweeten a cup of tea, and you have three types of sugar: sugar cubes (volume: 5ml), granulated sugar (volume: 0.1 ml), and powdered sugar (volume: 0.0001 ml). Which sugar would dissolve the fastest? Why?

Answers

Answer:

powdered sugar

Explanation:

The higher is the exposed area of sugar, the faster is the dissolution process. Thus, to choose between the different types of sugar, we have to look at the volume occupied by the sugar.

In sugar cubes, the particles of sugar as compacted in a cube, so the particles inside the cube are not exposed to the solvent (water). So, sugar cubes have the slowest dissolution process. Then, in granulated sugar, the particles have more area exposed, so this type of sugar will dissolve faster than sugar cubes. Finally, powdered sugar is composed of tiny particles with more are exposed, so powdered sugar has the fastest dissolution process.

Therefore, powdered sugar will dissolve the fastest.

33.0 g of Ni represents how many atoms?

1.99 x 10²⁵ atoms
0.562 atoms
3.39x 10²³ atoms
5.48 x 10^-23 atoms
3.22 x 10^-21 atoms​

Answers

Answer: 3.39 * 10^23

Use 33 grams (1 mol/58.69 grams) 6.02*10^23 to find the amount of atoms.

1. 33 grams (1 mol/58.69 grams) = 0.562276

2. 0.562276 * 6.02*10^23 = 3.3849 x 10^23

Since 33.0 has 3 sf, round the number above to 3sf, which would be 3.39 * 10^23 atoms

CH4 + 2 Cl₂ →→ 4 HCl + C
4. Use the equation above to calculate how many moles of CH4 are required to
produce 3.6 moles of HCl. (2 pts)

Answers

By using given equation 0.9 moles of CH₄ are required to produce 3.6 moles of HCl.

In simple terms, what is a chemical reaction?

The transformation of one or more reactants, also known as reactants, into one or more new products, also known as products, occurs during a chemical reaction.

Chemical reactions turn reactants into products by involving reactants in the process. As an illustration, when we breathe, oxygen is inhaled, and upon coming into contact with glucose, it reacts to create carbon dioxide, water, and energy.

Given chemical reaction:

CH₄ + 2 Cl₂ → 4 HCl + C

1 mole of CH₄ gives 4 moles of HCl

x moles of CH₄ gives 3.6 moles

x moles of CH₄ = 3.6/4

x moles of CH₄ = 0.9moles.

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Please show work image below includes the questions.

Answers

Answer:

Calcium nitride (Ca3N2)

148.25 g/mol is the molar mass

Which state of matter consists of particles that cannot be compressed and form a definite shape?
A. Gas
B. Liquid
C. Plasma
D. Solid

Answers

D.) “solid” is your answer

i apologize if i’m wrong

The solid does not consist of that particle which can not be compressed and have a definite shape.

What is solid?

One of matter's four basic states is solid. A solid's molecules are tightly packed and carry the minimum amount of kinetic energy. A solid's structural stiffness and resistance to a force applied to its surface define it. Although they are locked in fixed locations, they do vibrate. Solids have a defined structure and volume and cannot flow since the particles do not move. Solids are difficult to crush because the particles are often so close together.

What is particles?

A particle is a small, localized object to which numerous physical or chemical qualities, like volume, density, or mass, can be assigned.

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What particle has a negative electrical charge and is found in clouds
outside the nucleus? *
O Proton
O Neutron
O Electron

Answers

electrons

Revolving around the nucleus at a distance is a cloud of particles called electrons. Each electron has a negative charge.

Answer:

Electron

Explanation:

Because electrons are negatively charge particles

at what temperature will the mass of 198g of carbon dioxide gas at 2 atmospheric pressure take up to a volume of 35l? (gas constant= 0.0821L atm.​

Answers

Answer:

The temperature will be 189.70 K.

Explanation:

Ideal gases are a simplification of real gases that is done to study them more easily. It is considered to be formed by point particles, do not interact with each other and move randomly. It is also considered that the molecules of an ideal gas, in themselves, do not occupy any volume.

The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:  

P*V = n*R*T

where P is the gas pressure, V is the volume that occupies, T is its temperature, R is the ideal gas constant, and n is the number of moles of the gas. The universal constant of ideal gases R has the same value for all gaseous substances.

In this case:

P= 2 atmV= 35 Ln= 198 g* [tex]\frac{1 mole}{44 g}[/tex] = 4.5 moles (where 44 g/mole is the molar mass of carbon dioxide)R= 0.082 [tex]\frac{atm*L}{mol*K}[/tex]T= ?

Replacing:

2 atm* 35 L= 4.5 moles* 0.082 [tex]\frac{atm*L}{mol*K}[/tex] * T

Solving:

[tex]T=\frac{2 atm* 35 L}{4.5 moles* 0.082\frac{atm*L}{mol*K} }[/tex]

T= 189.70 K

The temperature will be 189.70 K.

How can you use chemical formulas to determine if a change is chemical or physical?

Answers

Answer: Chemical changes cause a substance to change into an entirely substance with a new chemical formula.

Physical changes only change the appearance of a substance, not its chemical composition.

Chemical changes are also known as chemical reactions.

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6. ( i’ll award the brainliest and any “links” will be reported)
sodium metal reacts with water and produces aqueous sodium hydroxide and hydrogen gas
a. Translate the word equation, and write the complete and balanced chemical equation.
b. What volume of hydrogen gas can be produced from reacting 5.67 grams of sodium metal with excess
water?
C. What is the percent yield if 964.00 mL of H, are collected through experimentation?

Answers

Answer: 2Na+2H2O------>2NaOH+H2

b) From the equation two moles of sodium gave one mole of hydrogen.

At stp the volume of hydrogen is 22400cm3.

The molar mass of sodium is 23

So we have

2molesNa--->1moleH2

5.76moles--->? mole H2

Meaning

2(23)Na----> 22400cm3 ofH2

5.67Na---->?H2

22400×5.67÷ 2(23)

127008÷46=2761.04cm3

Sorry I can't do the last one.

Draw plausible electron dot structures for the following substances. Each substance contains only single covalent bonds. A. I2 B. OF2 C.H2S D.NI3.

Answers

The plausible electron dot structures of I₂, OF₂, H₂S, NI₃ substances are attached below.

How is an electron dot structured?

Lewis dot structures, also known as electron dot structures, are diagrams that show how atoms in a molecule are chemically bonded to one another. They also show how many lone pairs there are in total among all the atoms that make up the molecule.

An electron configuration writing guide. The shell number (n) comes first in the symbols used to represent the electron configuration, followed by the type of orbital and, finally, a superscript that represents the number of electrons in the orbital. Examples include As you can see from the periodic table, oxygen has 8 electrons.

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Why are all of the elements in group 18 relatively un reactive whereas those in group 17 are very reactive?

Answers

All of the elements in group 18 are relatively un-reactive whereas those in group 17 are very reactive because group 18 elements have complete outer shell and group 17 needs only one electron to complete octet.

In the periodic table , the group 18 elements are called as the noble gases. the group 18 elements have the complete octet that mean the complete valence shell and they are stable due to which they are un reactive and also called as inert gases.

In the group 17 , the elements are called as halogens. the group 17 elements have the incomplete outer shell and they only need one electron to complete their octet due to which they are very reactive.

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The half-life of 90Sr is 29 years. What fraction of the atoms in a sample of 90Sr would remain 175 years later

Answers

Ninety-seven years is the half-life of 90Sr. A sample of 90Sr would still have 0.015 of its original atoms after 175 years. The duration needed for a quantity to fall to half its starting value is known as the half-life.

The phrase is frequently employed in nuclear physics to indicate how rapidly unstable atoms decay radioactively or how long stable atoms last. One or more electrons are attached to the nucleus of every atom, which is made up of a nucleus. Protons and neutrons, in various numbers, make up the nucleus. Neutrons exist only in the most prevalent type of hydrogen. Atoms that are neutral or ionised are the building blocks of all solids, liquids, gases, and plasma.

[A]t=[A]o/[A]t=4.18 [A]o/[A]t=e4.18=65.5

[A]o = 1.5%[A]o], where [A]t = 0.015

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