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Answer:

Polling is a method used for the purification of copper or tin which contains oxide impurities

Answer:

Polling is used for the purification of copper or tin which contains oxide impurities. The impure metal is melted and stirred with green logs of wood. The heat of molten metal makes the green logs to liberate hydrocarbon gases which in turn reduce the metal oxide into metal.

Answer:

The color of the light emitted depends on the energies of the photons emitted, which are in turn are determined by the energies required to move electrons from one orbital to another. Those colors are as distinctive to each element as fingerprints are to people. Hope this helps

Answer:

The color of the light emitted depends on the energies of the photons emitted, which are in turn are determined by the energies required to move electrons from one orbital to another. Depending on the element you put in the flame, various different energies of photons (colors) will appear. Those colors are as distinctive to each element as fingerprints are to people.

Explanation:

Answer:

Explanation:

La sal común es un compuesto iónico, es decir que sus átomos (Na y Cl) están unidos entre sí por fuerzas electrostáticas, y el metal está unido entre sí por uniones metálicas. La naturaleza de estas uniones es diferente y en base a las fuerzas de atracción que hay entre los átomos en compuestos con este tipo de uniones, la propiedades físicas generales serán diferentes.

En el caso de los metales, los átomos metálicos están colocados unos sobre otros de forma ordenada, pero no fijamente retenida, y los electrones de valencia están delocalizados a través de todo el cristal metálico. Por esta razón, cuando se le aplica una fuerza a un metal, estos átomos pueden deslizarse unos sobre otros. Ésta es la propiedad que le da a los metales su maleabilidad.

En el caso de los compuestos iónicos, los aniones y cationes que lo componen están ordenados en el cristal de una forma más rígida y por eso cuando se les aplica una fuerza éstos compuestos se rompen mucho más fácil, ya que no pueden deformarse.

Answer:

68000J/kg

Explanation:

Given parameters:

 Mass of the substance  = 0.5kg

 Quantity of heat transferred to the body  = 34000J

Unknown:

Specific latent heat of fusion = ?

Solution:

The specific latent heat is usually involve in phase changes;

  H  = mL

H is the quantity of heat supplied

m is the mass

L is the specific latent heat

 Insert the parameters and solve;

     34000 = 0.5 x L

         L  = [tex]\frac{34000}{0.5}[/tex]   = 68000J/kg

Answer:

b:   Neither atoms will have a full valence shell

Explanation:

I think sooo

Answer:

m(Ag) = 227.5g

Explanation:

...what is the mass of the piece of silver?

The heat given for the piece of silver is the same heat that is absorbed for the water, that is:

m(Ag)×C(Ag)×ΔT(Ag) = m(Water)×C(Water)×ΔT(Water)

m is mass of water in solution: 26.0mL = 26g of water

And m(Ag) is the mass of Ag, our incognite.

C is specific heat (0.240J/g°C for Ag), and 4.184J/g°C for water

ΔT is change in temperature (93.8°C - 44°C = 49.8°C) for Ag ad (44°C - 19°C = 25°C)

Replacing:

m(Ag)×C(Ag)×ΔT(Ag) = m(Water)×C(Water)×ΔT(Water)

m(Ag)×0.240J/g°C×49.8°C = 26g×4.184J/g°C×25°C

m(Ag)* 11.952J/g = 2719.6J

Answer:

C

Explanation:

Li has an electronegativity of 0.98, O has an electronegativity of 3.44. 3.44-0.98= 2.46 electronegativity differnece :)

Answer:

newton's firts law

Explanation:

because it states that everybody continue its state in rest unless an external force is appy to change its state from rest to motion.

Answer:

A, B, C

Explanation:

Answer:

a medium!!!!

Explanation:

ITS CORRECT!!!! I GOT IT RIGHT ON MY TESTTTTT! I PROMISEEE

Answer:

NH4

Explanation:

Answer:

Lithosphere plate boundaries are found in that area.

Explanation:

Answer:

C is the right answer

Explanation:

Answer:

what are you asking tho?

Explanation:

Thx for the Free points tho.

Answer:

a. 4.865 × 10⁻⁷ molecules. b. The possible health benefits of the drug might be minimal or non-existent.

Explanation:

a. Since we have 0.10 mol/L and 10 mL of solution, the number of moles in 10 mL of solution is n = CV where C = concentration and V = Volume. C = 0.10 mol/L and V = 10 mL = 0.01 L.

So n = CV = 0.10 mol/L × 0.01 L = 0.001 mol.

Since the initial volume of the solution is 10 mL and doubled, it is 2 × 10 mL = 20 mL. It is doubled again to 2 × 20 mL = 40 mL. It is doubled again to 2 × 40 mL = 80 mL. Our third doubling is thus 80 mL = 2 × 2 × 2 × 10 mL = 2³ × 10 mL. So the volume for our nth doubling is V = 2ⁿ × 10 mL. So four our 90 th doubling, the volume is V = 2⁹⁰ × 10 mL = 2⁹⁰ × 10 mL

Since we have 0.001 mol present, the concentration in this new volume is thus C' = 0.001 mol/2⁹⁰ × 10 mL.

So the number of moles in 10 mL of this solution is thus n = 0.001 mol/(2⁹⁰ × 10 mL) × 10 mL = 0.001/2⁹⁰ mol

To find the number of molecules of X present we use, number of moles, n = number of molecules, N/Avogadro's number of molecules, N'

n = N/N'

N = nN'

= 0.001/2⁹⁰ mol × 6.022 × 10²³ molecules/mol

= 8.078 × 10⁻³¹ × 6.022 × 10²³

= 48.65 × 10⁻⁸

= 4.865 × 10⁻⁷ molecules.

b. Since the number of molecules of X present in 10 mL solution of the final diluted solution is 4.865 × 10⁻⁷ molecules, this shows that the number of molecules of X is very little so, the possible health benefits of the drug might be minimal or non-existent.

Answer:

wind

Explanation:

it would be naturally caused by the pressure

Answer:

temperature or pressure differences

Explanation:

Answer:

A. They contain older stars and less gas and dust.

Explanation:

There are three types of galaxies:

Elliptical galaxies are galaxies shaped like an ellipse, while spiral galaxies consist of a flat, rotating disk that contains stars, gas, and dust, and a central concentration of stars called the bulge.

The difference between elliptical and spiral galaxies is in the amount of gas and dust they contain. Spiral galaxies contain large amounts of gas and dust, which means that new stars are born very often. This makes them brighter than relatively dim elliptical galaxies, which contain less gas and dust. This is why fewer new and brighter stars are born in elliptical galaxies, leaving them with older, dimmer stars.

Answer:

Hope this will help.......

Explanation Covalent bonds are insoluble in water (H2O) , but covalent compounds are. This is because some organic compounds (covalent) contain the polar −OH group which can bond to a hydrogen ion to form water.

Answer:

We can seperate a mixture by various methods

Explanation:

Distillation, Evaporation, filtration and chromatography

Explanation:

Molar mass of Ba(NO3)2 = 261.3368 g/mol

Answer:

Try searching this on google

Explanation:

I might have an answer but I am not entirely sure sorry I really tried to help but there is also an app called socractic it also helps with questions

Once the temperature reaches 15,000,000 levels Celsius, nuclear fusion takes location in the center, or core, of the cloud. The high-quality heat given off by means of the nuclear fusion technique motives the gasoline to glow creating a protostar. This is the first step in the evolution of a star.

Answer:

i think just these

NaCl

CaCl2

The elements that have least protons to those having the most protons in the atoms are:

B. C, Al, P, Cl

There is an equal number of protons and electrons in an atom. So when moving across a period in a periodic table the number of electrons increases which also shows the increases in a number of protons. So as the atomic number increases, the number of protons and electrons also increases.

Thus, the order of elements having least to greatest protons are:

C, Al, P, Cl

C has 6 atomic number, Aluminium has 13 atomic number , Phosphorus has 14 atomic number and atomic number of chlorine is 17.

Thus, option B is correct.

Find more information about Atomic number here:

brainly.com/question/1805828

Answer:

the 2 means there are 2 al and the 3 means there are 3 o

Explanation:

I hope this helps