*(d) Impure copper can be purified using electrolysis.
In this electrolysis
• the anode is made of impure copper
• the cathode is made from pure copper
• the electrolyte is copper sulfate solution.
The apparatus at the start of the experiment is shown in Figure 7.

During the electrolysis three observations are made

• the sizes of both the anode and the cathode change

• a solid appears directly beneath the anode

• the colour of the copper sulfate solution does not change.
Explain all three observations.
​

i will give u brainliest if u get it right

Answer:

Answer:

[tex]36.273\ \text{kJ/mol}[/tex]

Explanation:

m = Mass of LiCl = 2.5 g

M = Molar mass of LiCl = 42.394 g/mol

c = Specific heat of water = [tex]4.186\ \text{J/g}^{\circ}\text{C}[/tex]

[tex]\Delta T[/tex] = Change in temperature = [tex]29.11-24=5.11\ ^{\circ}\text{C}[/tex]

[tex]m_w[/tex] = Mass of water = [tex]\rho V=1\times 100=100\ \text{g}[/tex]

Number of moles

[tex]n=\dfrac{m}{M}\\\Rightarrow n=\dfrac{2.5}{42.394}\\\Rightarrow n=0.05897\ \text{mol}[/tex]

Heat is given by

[tex]Q=m_wc\Delta T\\\Rightarrow Q=100\times 4.186\times 5.11\\\Rightarrow Q=2139.046\ \text{J}[/tex]

Enthalpy is given by

[tex]\Delta H=\dfrac{Q}{n}\\\Rightarrow \Delta H=\dfrac{2139.046}{0.05897}\\\Rightarrow \Delta H=36273.46\ \text{J/mol}=36.273\ \text{kJ/mol}[/tex]

The enthalpy for the dissolution is [tex]36.273\ \text{kJ/mol}[/tex].

Answer:

im pretty sure its the second one

Answer:

It must be neutral because there are 9 positive atoms and 9 megative charged atoms they cancels each other out and make the particle neutral

Explanation:

I hope this helps!!

Answer:

B. metals

Explanation:

Most of the elements in the periodic table are classified as metals. They are usually solid at room temperature.

Answer:

21%

Explanation:

It's a mixture of different gases. The air in Earth's atmosphere is made up of approximately 78 percent nitrogen and 21 percent oxygen.

Answer:

a Hg(NO3)2

b CoBr2,CoBr2·6H2O,CoBr2·2H2O

Explanation:

Answer:

because the neutrons is always equal or greater there is never a less then in neutrons.

Explanation:hope this helped

Answer:

Dmitri Mendeleev

Explanation:

Dmitri Mendeleev a Russian Chemist arranged elements on the periodic table according to their atomic mass. He used this arrangement to predict some of the properties of the missing element.

Answer: Copper in Chemisry is an chemical element, a reddish, extremely ductile metal of Group 11 (Ib) of the periodic table that is an unusually good conductor of electricity and heat. Copper is found in the free metallic state in nature.

Explanation:

Answer:

Grating

Explanation:

I think you need to grate it

Answer: The sugar would dissolve in water. You could then pour off the solution and wash the remaining sand with a bit more water. Heat the water to evaporate it from the sugar, and the two are separate

Explanation:

Answer:

I'm pretty sure it is unbalanced

Answer:

A.

General Formulas and Concepts:

Chemistry - Stoichiometry

Explanation:

Step 1: Define

Given:   4 mol Mg(OH)₂

RxN:   MgCl₂ + 2KOH → Mg(OH)₂ + 2KCl

Step 2: Identify Conversions

Molar Mass of K - 39.10 g/mol

Molar mass of O - 16.00 g/mol

Molar mass of H - 1.01 g/mol

Molar Mass of KOH - 39.10 + 16.00 + 1.01 = 56.11 g/mol

Step 3: Stoichiometry

[tex]4 \ mol \ Mg(OH)_2(\frac{2 \ mol \ KOH}{1 \ mol \ Mg(OH)_2} )(\frac{56.11 \ g \ KOH}{1 \ mol \ KOH} )[/tex]

Answer:

check the attachment/picture below!

Explanation:

I had just taken that quiz! :D

Answer:

b

Explanation:

Answer:

second rock...I know it

Answer:

1.23345*10^11

5.768*10^(-5)

3.456*10^(-2)

2.28*10^9

8.0970*10^4

Explanation:

You just need to count the number of zeros and move the values backward and forward to get the scientific notation.

Answer:

The answer is Boling Point

Explanation:

The properties of the sample which is most helpful to determine if the liquid is water is (D) . the boiling point of the liquid

The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor.

The boiling point of a liquid varies depending upon the surrounding environmental pressure

Substances at different states usually possess certain properties that distinguishes them. For example, in this case involving a student who was given a sample of an unknown liquid to test in the laboratory, he thinks that the unknown liquid is water.

Specific properties of the unknown liquid can be used to identify whether it is water or not.

One property that can be used to ascertain whether or not it is water is the boiling point of the liquid. This is because specific liquids have specific boiling point. So if the unknown liquid has a boiling point of 100°C, then it can be ascertained to be water.

Therefore, The properties of the sample which is most helpful to determine if the liquid is water is (D) . the boiling point of the liquid

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Answer:

ethylene molecule. The molecule has trigonal planar geometry around its carbon atoms

Answer:

A wave with a higher frequency have a shorter wavelength, the higher the sound it, the closer the arcs of the wavelength are, the faster the sound is, the shorter they are.

According to scied.ucar.edu  ~  "The frequency of a wave is inversely proportional to its wavelength. That means that waves with a high frequency have a short wavelength, while waves with a low frequency have a longer wavelength. Light waves have very, very short wavelengths."

Hope this helps

Explanation:

May I have brainliest please? :)

A wave with a higher frequency has a longer wavelength is a false.

A wave with a higher frequency has a longer wavelength is a false statement because shorter wavelength have higher frequency and also higher energy.

We know that longer wavelength of a wave having shorter frequency and shorter energy while on the other hand, the shorter wavelength of a wave having higher frequency and higher energy so we can conclude that the statement is false.

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Mass of oxygen : 54 g

Conservation of mass applies to a closed system, where the masses before and after the reaction are the same

Reaction

[tex]\tt C+O_2\rightarrow CO_2[/tex]

mass before reaction = mass after reaction

mass C + mass O₂= mass CO₂

[tex]\tt 18~g+mass~O_2=72~g\\\\mass~O_2=72-18=\boxed{\bold{54~g}}[/tex]

Answer:

Li atoms readily give up one electron to form positively charged, Li+ ions. These ions have the same stable electron configuration as the noble gas helium. All Group 1 atoms can lose one electron to form positively charged ions.

Explanation:

I DON'T KNOW IF THIS IS THE RIGHT ANSWER BUT I'M TRYING TO JUST ANSWER.

Answer:

Explanation:

-We know that an atom is table if they have 8 valence electrons (like noble gases, they are stable)

-Group 1 atoms only has 1 valence electron, in order to become stable, they are desperately wanted to lose that one valence electron to become stable.

-While group 15 has 5 electrons, it is easier for them to gain 3 electrons to become 8 electrons than losing all 5 electrons.

-the same thing for group 16 has 6 valence electrons and 17 has 7 electrons. It is easier for them to gain 2 and 1 more valence electrons to become stable.

Hope this helps!

Answer:

Kinetic energy is the energy possessed by an object in motion.

Answer:

at the center of the mid-ocean ridge

Explanation:

Answer:

Anywhere along the mid-atlantic ridge

Explanation:

It goes through a bunch of history, such as the Continental Drift Theory from Alfred Wegener to Harry Hess proving it. So, in WW2, Harry Hess was in the navy (he was a geographer/geologist who noticed while using sonar, that the waves were bouncing back uneven when they launched sonar, which proved the ocean floor was not flat like how they used to beleive it was.

Anyways, they discovered the mid-atlantic ridge, (you can see it on maps! Go to a search engine's maps and look at the atlantic ocean and you can see this weird ridges along with these (not latitude or longitude) lines.

The mantle in the Earth's layers is moving the plates (continental and oceanic plates to be exact) from convection currents, and there is very deep trenches in the Earth, such as the Mariana Trench. The mantle pushes magma through some holes, and it rises and cools in the ocean, which is then pushed aside by more solidifiying magma in a process called seafloor spreading. Magma is called lava when it comes out of the place where it comes from, so the lava cools into rock which is called basalt too.

Hope this helps anyone in the future!

I don't mean to be a boomer by necroposting

dont roast me plz

Answer:

4Al (s) + 3O₂ (g) → 2Al₂O₃

General Formulas and Concepts:

Chemistry - Reactions

Explanation:

Step 1: Define RxN

Al (s) + O₂ (g) → Al₂O₃

Step 2: Balance RxN

4Al (s) + 3O₂ (g) → 2Al₂O₃

If the force is applied to lift the box, then there is no work done as the displacement of the box is not in the same direction of the box.

However, if the force is being applied to move the box in the direction of the force, then the work done is:

Work = force x distance

Work = 1500 x 3

Work = 4,500 Joules

A forklift applies a force of 2,000 N to raise a box 3 m. The work is done by the forklift in raising the box is 6000 Joules.

A force is an influence that has the power to alter an object's motion. An object with mass can change its velocity, or accelerate, as a result of a force. An obvious way to describe force is as a push or a pull. A force is a vector quantity, since it has both magnitude and direction.

Isaac Newton's three laws of motion, which are outlined in his Principia Mathematica, are frequently used to illustrate the concept of force (1687).

Contact forces and act at a distance forces are the two different types of forces. Your daily use of force is evident. Basically, push and pull are forces. You exert force on an object when you push against it or pull against it.

The force is applied to move the box in the direction of the force,

Then the work done is

Work = force x distance

Work = 2000 x 3

Work = 6000 Joules.

Thus, A forklift applies a force of 2,000 N to raise a box 3 m. The work is done by the forklift in raising the box is 6000 Joules.

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Answer:

Explanation:

To convert a temperature from degree Celsius to Kelvin add 273 to the value in degree Celsius

That's

K = 273 + °C

where

K is the temperature in Kelvin

°C is the temperature in degree Celsius

From the question we have

K = 273 + 133

We have the final answer as

Hope this helps you