Need help will mark brainliest!!

Answer:

In chemistry, a mixture is a material made up of two or more different substances which are not chemically combined. ... A mixture is the physical combination of two or more substances in which the identities are retained and are mixed in the form of solutions, suspensions and colloids.

Answer:

The answer is C

Explanation:

I did look it up, the other kid just spams random bs for points, hope you didn't get it wrong because of him! :)

Answer:

6.5x10⁻³M = [OH⁻]

Explanation:

The Kb of a Weak base as ethylamine is expressed as follows:

Kb = [OH⁻] [C₂H₅NH₃⁺] / [C₂H₅NH₂]

As the equilibrium of ethylenamine is:

C₂H₅NH₂(aq) + H₂O(l) ⇄ C₂H₅NH₃⁺(aq) + OH(aq)

The concentration of C₂H₅NH₃⁺(aq) + OH(aq) is the same because both ions comes from the same equilibrium. Thus, we can write:

Kb = [OH⁻] [C₂H₅NH₃⁺] / [C₂H₅NH₂]

6.4x10⁻⁴ = [X] [X] / [C₂H₅NH₂]

Also, we can assume the concentration of ethylamine doesn't decrease. Replacing:

6.4x10⁻⁴ = [X] [X] / [0.066M]

4.224x10⁻⁵ = X²

6.5x10⁻³M = X

The molar concentration of OH ions in a 0.066 M solution of ethyl amine is [tex]6.5x10^-^3M[/tex]

Molar concentration is the measure of the concentration of the chemical species present in any solution.

Step1: Calculating The Kb

[tex]Kb = [OH^-]\dfrac{ [C_2H_5NH_3^+] }{[C_2H_5NH_2]}[/tex]

As the equilibrium of ethyl amine is:

[tex]\rm C_2H_5NH_2(aq) + H_2O(l) <-> C_2H_5NH_2^+(aq) + OH(aq)[/tex]

[tex]Kb = [OH^-]\dfrac{ [C_2H_5NH_3^+] }{[C_2H_5NH_2]}[/tex]

[tex]6.4\times10^-^4 = \dfrac{ [X][X]}{[C_2H_5NH_2]}[/tex]

The concentration of ethyl amine does not decrease.

[tex]\rm 6.4\times10^-^4 = \dfrac{ [X][X]}{0.066\;M}[/tex]

[tex]4.224\times10^-^5 = X^2[/tex]

[tex]6.5x10^-^3M = X\\\\6.5x10^-^3M = [OH^-][/tex]

Thus, the molar concentration is [tex]6.5x10^-^3M[/tex]

Learn more about molar concentration, here:

https://brainly.com/question/5986539

Answer:

the atomic number of the atom can be determine through the number of protons in the nucleus

The protons are usually the atomic number.

Answer:

Explained below.

Explanation:

From avogadro's number, we know that;

1 mole = 6.022 × 10^(23) atoms, molecules, protons e.t.c.

Now,to convert from atoms, compounds, formula units, etc to moles, what we will do is just to divide the amount of the particle value given in the specific units by avogadro's number.

For example, to convert 23 × 10^(20) atoms to moles, we will have;

Number of moles = (23 × 10^(20))/(6.022 × 10^(23)) moles = 0.00382 moles

Answer:

Aerobic Energy System

Explanation:

Answer:

Digestive system. It contains chemical energy. The digestive system breaks down food. Food contains chemical energy. To break down the food, the digestive system contains enzymes. Enzymes have kinetic energy to move and break down the food. They are biological catalysts. They transfer to the thermal energy store since in order to break down food at the fastest rate, they need to be at an optimum temperature.

I'm not sure if it's correct, but I'll provide some energy stores to give you inspiration:

Kinetic energy

Chemical energy

Nuclear energy

Gravitational potential energy

Elastic potential energy

Thermal energy

Answer:

magnesium + oxygen = magnesium oxide

Explanation:

the word equation for molecules of magnesium reacting with molecules of oxygen to produce molecules of magnesium oxide is magnesium  oxygen  magnesium oxide.

Answer:

It could pollute other planets. Nuclear waste might be attracted by the gravitational pull of the sun and disintegrate there instead. The waste storage spacecraft could crash into a planet, moon, or another astronomical body. It could be dangerous for other life forms out there.

Explanation:

Answer:

The structure of the atom.

Explanation:

The correct answer is - The structure of the atom.

Reason -

An atom is the smallest unit of matter that retains all of the chemical properties of an element.

Answer:

answer

Explanation:

explination

Answer:

B. Non-metals

Explanation:

The element with the atomic number of 17 is Cl.

Chlorine belongs to the group 7 in the periodic table. It is a non metal.

Correct option: B. Non-metals

Answer:

no volume does not

Explanation:

Answer:

0.0578647982046175

Explanation:

Answer: C planets dont travel in perfect circles and they do not orbit earth they orbit the sun and they ellipse around the sun. this is the correct answer do not lsiten to the other person

Explanation:

The statement which is correct about planetary orbits is the planets travel in ellipses around the sun.

Orbits is the path of the motion, in which planets do revolutionary motion in a particular sequence.

In the solar system, sun is present at the center and all the planets do revolution around the sun in their orbits which are ellipse in their shape. Elliptical shape of the orbits is due the large distance of planets from the sun which reduces the speed due to less gravitational force of sun on that object.

Hence, option (C) is correct i.e. The planets travel in ellipses around the sun.

To know more about orbits, visit the below link:
https://brainly.com/question/855117

Answer:

hi

Explanation:

Explanation:

substance Q could be oxygen (O2)

substance R could be carbon dioxide (CO2)

Substance Q could be oxygen ([tex]O_2[/tex])

Substance R could be carbon dioxide ([tex]CO_2[/tex])

The smallest particle of a substance that has all of the physical and chemical properties of that substance.

There are 2 oxygen atoms in 1 molecule of oxygen. It is a di-atomic gas.

Carbon dioxide is a chemical compound composed two oxygen atoms covalently bonded to one carbon atom.

Hence, substance Q could be oxygen ([tex]O_2[/tex]). substance R could be carbon dioxide ([tex]CO_2[/tex])

Learn more about molecules here:

https://brainly.com/question/14130817

#SPJ2

Answer:

In a solid, they're really close together and vibrate a LITTLE, in a liquid they're kinda close together but change movement because water will change shape depending on the container they're in. For gas they are spread far from each other and vibrate A LOT

Explanation:

Answer:

The number of protons and neutrons.

Explanation:

Neutrons and Protons can't be removed from nucleus from chemical reactions because they are held together super strong and tight. However, nuclear reactions are strong enough to separate them.

hope this helps :)

Answer:

The number of protons and neutrons

Explanation:

Answer:

Calcium hydroxide + Carbon dioxide → Calcium carbonate + Water

(b) Zinc + Silver nitrate → Zinc nitrate + Silver

(c) Aluminium + Copper chloride → Aluminium chloride + Copper

(d) Barium chloride + Potassium sulphate → Barium sulphate + Potassium chlorid

Explanation:

Answer:What is used up in and stops a chemical reaction? (a) percent yield (b) limiting reactant (c) theoretical yield (d) excess reactant

The correct option is (b)

Explanation:

A chemical reaction is a chemical combination,rearrangement or disintegration of chemical substance(s) (called reactants) to form new chemical substance(s) (called products).

A limiting reactant is the reactant that is totally used up during the course of a reaction. When this reactant is used up, it limits the amount of products formed and eventually stops the chemical reaction.

Explanation:

The limiting reagent is the reactant that is used up completely. This stops the reaction and no further products are made. ... This method is most useful when there are only two reactants. The limiting reagent can also be derived by comparing the amount of products that can be formed from each reactant.

hope this helps have a nice day❤️

Answer:

it disappeared loll jk

it obviously dried

well you may Mark me as brainliest

Answer:

1. A

2. B

3. D

4. C

Explanation:

Just trust me. Good luck on your test! (I go to K12 as well.)

Answer: D. 434 K

Explanation:

To calculate the final temperature of the system, we use the equation given by Charles' Law. This law states that volume of the gas is directly proportional to the temperature of the gas at constant pressure.

Mathematically,

[tex]\frac{V_1}{T_1}=\frac{V_2}{T_2}[/tex]

where,

[tex]V_1\text{ and }T_1[/tex] are the initial volume and temperature of the gas.

[tex]V_2\text{ and }T_2[/tex] are the final volume and temperature of the gas.

We are given:

[tex]V_1=606ml\\T_1=35^oC=(35+273)K=308K\\V_2=854ml\\T_2=?[/tex]

Putting values in above equation, we get:

[tex]\frac{606}{308}=\frac{854}{T_2}\\\\T_2=434K[/tex]

Thus  temperature necessary for the  gas to have a volume of 854 ml is 434 K

M1V1 = M2V2

M1 = 0.23 M HCl

V1 = 35 mL

M2 = 0.3 M NaOH

V2 = ?

(0.23 M)(35 mL) = (0.3 M)V2 —> V2 = 27 mL NaOH

Answer:

The correct answer to your Question is B.

Explanation:

Hope you have a great day :)

The substance from the options that will dissolve most rapidly is : ( B ) Powdered sugar in hot water.

Increase in temperature, state of solute and volume will determine the rate at which solubility occurs. The powdered sugar is in less solid state when compared to sugar cubes and therefore will dissolve most rapidly in hot water than a sugar cubes in hot water.

Hence we can conclude that The substance from the options that will dissolve most rapidly is : ( B ) Powdered sugar in hot water.

Learn more about solubility : https://brainly.com/question/23946616

#SPJ2

Answer:

16.6 g of Al are produced in the reaction of 82.4 g of AlCl₃

Explanation:

Let's see the decomposition reaction:

2AlCl₃ →  2Al  + 3Cl₂

2 moles of aluminum chloride decompose to 2 moles of solid Al and 3 moles of chlorine gas.

We determine the moles of salt:

82.4 g . 1mol/ 133.34g = 0.618 moles

Ratio is 2:2. 2 moles of salt, can produce 2 moles of Al

Then, 0.618 moles of salt must produce 0.618 moles of Al.

Let's convert the moles to mass → 0.618 mol . 26.98g /mol = 16.6 g