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Which describes an attribute of nonrenewable resources?
A.) exist in fixed amounts
B.) are unlimited
C.) can often be replaced in a short time
D.) are replaced faster than they are used

Answer:

the Recrystallization solvents are;

-Sodium Hydroxide Base (NaOH)

- Hydrochloric Acid (HCl)

- Sand bath when acidic and basic components are removed.

Explanation:

Recrystallization is simply a technique used to purify an impure compound in a solvent.

Now, we want to purify the mixture of benzoic acid, Ethyl-4-aminobenzoate and fluorenone.

For the benzoic acid, it can be separated out of the mixture by addition of sodium hydroxide base (NaOH).

The Ethyl - 4 - aminobenzoate will be separated from the mixture by the addition of Hydrochloric Acid (HCl).

The fluorenone would be separated out by heating the mixture in a sand bath after the basic and acidic components have already been extracted out.

Thus, the Recrystallization solvents are;

-Sodium Hydroxide Base (NaOH)

- Hydrochloric Acid (HCl)

- Sand bath when acidic and basic components are removed.

Answer:

Answer:

Be

Explanation:

The atomic radius decreases as you go from left to right in a period. Be has the largest radius out of those given elements.

Answer:

false you can not get a exact location of electrons from just modern science

Answer:

2.4g of NaClO must be added

Explanation:

To find the pH of a buffer we must use H-H equation:

pH = pKa + log [A⁻] / [HA]

Where pH is the pH of the buffer, 7.35

pKa of the HClO buffer is 7.54

[A⁻] could be taken as moles of NaClO

And [HA] moles of the weak acid: 500mL = 0.500L * (0.1mol/L) = 0.05 moles

Replacing:

pH = pKa + log [A⁻] / [HA]

7.35 = 7.54 + log [A⁻] / [0.05moles]

0.6457 = [A⁻] / [0.05moles]

0.03228 moles = Moles of NaClO we need to make the pH = 7.35 buffer.

To convert these moles to grams we use the molar mass of NaClO (74.44g/mol):

0.03228 moles * (74.44g/mol) =

Answer:

The answer is D - Atom

The smallest unit of an element that can exist either alone or in combination with other such particles of the same or different elements is the atom.

An atom is defined as the smallest unit of matter which forms an element. Every form of matter whether solid,liquid , gas consists of atoms . Each atom has a nucleus which is composed of protons and neutrons and shells in which the electrons revolve.

The protons are positively charged and neutrons are neutral and hence the nucleus is positively charged. The electrons which revolve around the nucleus are negatively charged and hence the atom as a whole is neutral and stable due to presence of oppositely charged particles.

Atoms of the same element are similar as they have number of sub- atomic particles which on combination do not alter the chemical properties of the substances.

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Answer:

the fish can't survive in that warm water

Explanation:

when the factory puts that warm water into the stream where the fish live they changed their environment. by adding unknown chemicals and changing the temp of the water the fish start to die.

The fish aren't used to living in that warm water, and if they can't adapt fast enough they will die, also the unknown chemicals that could be in the water will act as a poison for them making that stream unable to support any life.

Answer:

A

Explanation:

As the space in a container gets, smaller the volume decreases because volume is a measure of the space that the particles can occupies inside.

Volume is the space occupied by a substance and which is directly proportional to temperature according to Boyles law and inversely proportional to the pressure.

As the temperature increases, volume increases whereas the pressure increases, volume get decreased.  As there are more particles but the space inside a container is small, then their volume is said to be smaller.

Hence, option C is the answer.

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Answer:

Which one of the table is element X?

Explanation:

I have no idea and help!!!!!!!!!!!!!!!!!!!!!!!!!

Answer:

t = 7.58 * 10¹⁹ seconds

Explanation:

First order rate constant is given as,

k =  (2.303 /t) log  [A₀] /[Aₙ]

where  [A₀]  is the initial concentraion of the reactant; [Aₙ] is the concentration of the reactant at time, t

[A₀]  = 615 calories;

[Aₙ] = 615 - 480 = 135 calories

k = 2.00 * 10⁻²⁰ sec⁻¹

substituting the values in the equation of the rate constant;

2.00 * 10⁻²⁰ sec⁻¹ = (2.303/t) log (615/135)

(2.00 * 10⁻²⁰ sec⁻¹) / log (615/135) = (2.303/t)

t = 2.303 / 3.037 * 10⁻²⁰

t = 7.58 * 10¹⁹ seconds

Analysing the question:

To calculate the density of a material, we need its mass and volume

We are given:

Mass of sample = 21 grams

dimensions of the sample = 1 * 1 * 2 = 2 cm³

Calculating the density:

Density = Mass of sample / volume of sample

Replacing the variables

Density = 21 / 2

Density  = 10.5 g / cm³

Determining the Material:

From the table provided, we can see that the density of Silver is 10.5 g/cm³

Therefore, the material is Silver

Answer:

Protons are always found in the nucleus of an atom.

Explanation:

Protons and neutrons make up the nucleus of an atom, which is in the center. The electrons "orbit" the nucleus.

Answer:

The number of protons, neutrons, and electrons in an atom can be determined from a set of simple rules.

Explanation:

The number of protons in the nucleus of the atom is equal to the atomic number (z). The number of electrons in a neutral atom is equal to the number of protons.

Answer:

Compared to the walls of the right ventricle, the walls of the left ventricles are much thicker.

The plasma carries hormones, which are the body's chemical messengers.

Answer:

2.528x10⁻³M

Explanation:

Molarity is an unit of concentration used in chemistry. Is defined as the moles of solute per liter of solution.

To find the molarity of the solution we need to determine the moles of ammonium sulfate present in the initial 49.16mL solution and, with total volume, we can find the molarity, thus:

Moles ammonium sulfate:

49.16mL = 0.04916L * (0.0270 moles / L) =

1.327x10⁻³moles ammonium sulfate

These moles are present in 525.0mL = 0.525L. Thus, molarity of the solution will be:

1.327x10⁻³moles ammonium sulfate / 0.525L =

Answer:

The elements with completely filled shells are classified as noble gases

That is why we only see noble gases on the rightmost corner of the periodic table, it is because they have the maximum number of electrons in a shell

Examples of noble gases

Helium , Neon , Argon and Krypton are some examples of noble gases

Answer:

Explanation:

I JUST TOOK THE TEST!

Answer:

Explanation:

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

[tex]volume = \frac{mass}{density} \\ [/tex]

From the question we have

[tex]volume = \frac{244}{2.7} \\ = 90.370370...[/tex]

We have the final answer as

Hope this helps you

Answer:

A. It occupies 22.4 L

Explanation:

STP (Standard Conditions for Temperature and Pressure) = 22.4 L per mole at 1 atm

Avogadro's Law states that 1 mol at 1 atm occupies 22.4 L.

Explanation:Thermal energy, or heat, is the energy that comes from the movement of atoms and molecules in a substance. Heat increases when these particles move faster. Geothermal energy is the thermal energy in the earth. Motion energy is energy stored in the movement of objects.

I hope this helped!

Answer:

this

Explanation:

What is the unit rate of the better deal? (Number answers only.)

LaTeX: \frac{160\:miles}{5\:gallons}\:or\:\frac{315\:miles}{9\:gallons}160 m i l e s 5 g a l l o n s o r 315 m i l e s 9 g a l l o n s

The better deal has a unit rate of [m] miles per gallon.

And we can see that the potassium ion, K+, has the same electronic configuration as the chloride ion, Cl-, and the same electronic configuration as an atom of argon, Ar. Therefore, Ar, Cl-, and K+ are said to be isoelectronic species.

Answer:

A landform is a feature on the Earth's surface that is part of the terrain. Mountains, hills, plateaus, and plains are the four major types of landforms. Minor landforms include buttes, canyons, valleys, and basins. Tectonic plate movement under the Earth can create landforms by pushing up mountains and hills.

Explanation:

"Waterways" are the other large features that cover the surface of the earth.

A canal would be any body of water throughout which boats may move. Waterways, on the other hand, comprise waterways that seem to be expansive as well as shallow enough already to allow freight-carrying watercraft just to travel through.

Some bodies of water are usually regularly dredged to maintain an appropriately deep course throughout all circumstances. Dams change the depth of other rivers in particular parts.

Thus the response above i.e., "Option B" is correct.

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Answer:

POTASSIUM

Explanation:

2 8 8 1________ 1A

This question is incomplete, the complete question is;

Tonksite is a solid at 300.00K.  At 300.00 K its enthalpy of sublimation is 66.00 kJ/mol. The sublimation pressure at 300.00 K is 5.00 × 10⁻⁴ atm

Calculate the sublimation pressure of the solid at the melting point of 400.00 K assuming that the enthalpy of sublimation is not a function of temperature.

Answer: the sublimation pressure of the solid at the melting point is  0.3727 atm

Explanation:

Given that;

T1 = 300 K

T2 = 400 K

H_sub = 66 kJ/mol = 66000 J/mol

P1 = 5.00 × 10⁻⁴ atm

p2 = ?

now using the expression

log( p2 / 5.00 × 10⁻⁴ ) = (H_sub / R ×  2.303 ) (( T2 - T1) / T1T2)

now we substitute of given values into the expression

log(p2/p1) = (66000 / 8.314 ×  2.303 ) (( 400 - 300) / 300 × 400 )

p2 = 0.3727 atm

therefore the sublimation pressure of the solid at the melting point is  0.3727 atm