why concentrated acid is hazardous material​

Answer:

The traditional electrolyte for aluminium electrolysis is based on molten cryolite (Na3AlF6), acting as solvent for the raw material, alumina (Al2O3).Metals are found in ores combined with other elements. Electrolysis can be used to extract a more reactive metal from the ore.

Aluminum can and is used as both anodes and cathodes in electrochemical cells, but there are some peculiarities to using it as an anode in aqueous solutions. As you note, aluminum forms a passivating oxide layer quite readily, even by exposure to atmosphere. In an aqueous solution, if the potential is high enough, OH− and O2− are generated at the anode, which can then react with the aluminum to produce aluminum oxide. Al^3+ can also be generated directly. The electric field will draw the anions through the growing aluminum oxide layer towards the aluminum surface and the Al^3+ towards the solution, making the oxide layer grow both away from the electrode surface and into the surface of the electrode. In this way, coatings thicker than the normal passivation in air can be produced. However, aluminum oxide is a good electrical insulator, thus if a dense non-porous layer is grown, it will become impossible to pass current through it and growth will stop, leaving a relatively thin oxide layer (this is how the dielectric layers in electrolytic capacitors are made). This is the normal behaviour in aqueous solutions at near-neutral pH (5–7).

However, if a thick aluminum oxide layer is desired (e.g. to produce coatings on aluminum parts for dying or durability), maintaining porosity is necessary to avoid completely blocking access to the surface. One technique that is commonly used is using a low pH solution, which tends to redissolve some of the oxide and neutralize some of the formed OH−, leaving pores in the oxide layer through which the ions can travel and continue to react. These pores also give a good structure to retain dyes or lubricants, but generally need to be sealed after to protect against corrosion.

Answer:

Fluroine

Explanation:

Answer:

Fluorine

Explanation:

Nitrogen atomic radius: 155 pm

Oxygen atomic radius: 152 pm

Fluorine atomic radius: 147 pm

Carbon atomic radius: 170 pm

Therefore, fluorine has the smallest atomic radius.

Answer:

55.845

Explanation:

yep

Answer:

8% thymine

Explanation:

The percent of thymine in the given sample of the DNA will be equal to 8 %.

DNA, according to Chargaff, is composed of nucleotide subunits. These nucleotides are linked through two or more hydrogen-bonded to one another to form the double-stranded molecule of DNA.

The nucleotides found in the DNA molecule are Adenine, Thymine, Cytosine, and Guanine. Guanine (G) pairs with Cytosine (C) while  Adenine (A) pairs with Thymine (T).

According to Chargaff's rule, the amount of Adenine is equal to that of Thymine in a DNA molecule and the same applies to Guanine and Cytosine. We can consider that the total amount of nucleotides equals 1 or 100%.

[tex]A + T + G + C = 100\%[/tex]

If Cytosine is 42 % of the DNA sample, this means that guanine will also be  42%.

G + C = 42 + 42  = 84%

A + T = 100% - 84 % = 16%

This means that Adenine and Thymine amount to 16 %. The amount of each nucleotide will be 16% ÷ 2 = 12% i.e. A = T = 8 %

Therefore, the percent of thymine in the given sample of the DNA will be 8 %.

Learn more about the structure of DNA, here:

https://brainly.com/question/22499464

#SPJ2

Answer:

i think it's freezing of permafrost. so sorry if it's wrong lol

Yes,I agree that it is a redox reaction.

In the given reaction potassium metal is placed in water and when a reactive metal is placed in water, it reacts with water to form metal hydroxide and hydrogen gas, as a result, potassium hydroxide and hydrogen gas are produced in the reaction.

A redox reaction is a reaction in which a substance is oxidized during the reaction whereas some other substance is reduced during the reaction, simultaneously.

The given chemical reaction is:

2K(s) + 2H20(l) arrow 2KOH(aq) + H2(g)

Learn more :

https://brainly.com/question/24095220?referrer=searchResults

Answer:

In the given reaction potassium metal is placed in water and when a reactive metal is placed in water, it reacts with water to form metal hydroxide and hydrogen gas, as a result, potassium hydroxide and hydrogen gas are produced in the reaction.

Explanation:

Answer:

The bottle is labeled pure so it probably is pure.

Explanation:

Answer:

Here's ur answer

Explanation:

Answer:

C. Particle size

Explanation:

The sand, which has smaller particles, will go through the sieve, while the rice (with a larger particle size) will not

Answer:

Explanation:

Building Vocabulary

Match each term with its definition by writing the letter of the correct definition on

the line beside the term in the left column.

5. nucleus   b

6. proton     f

7. neutron   h

8. electron  d

9. atomic number    g

10. isotopes              c

11. mass number      a

12. energy level       e

a. the sum of protons and neutrons in the nucleus of an

atom

b. the very small center core of an atom

c. atoms of the same element that differ in the number

of neutrons, but have the same number of protons

d. the particle of an atom that moves rapidly in the

space outside the nucleus

e. a specific amount of energy related to the movement

of electrons in atoms

f. the particle of an atom with a positive charge

g. the number of protons in the nucleus of every atom

of an element

h. the particle of an atom that is neutral

-. mass number  a.

12. energy level    e

mjhhhhhhhhhhmmmmnnñbb

Answer:

A catalyst

Catalysts speed up the rate of reaction without being changed or used up in the reaction.

Hope this helps!

Answer:

Introduction to Basic Microscopy. Microscopes are specialized optical instruments designed to produce magnified visual or photographic (including digital) images of objects or specimens that are too small to be seen with the naked eye.

Microscope are the important tools which are used by scientist. For example, in material science, medicine, mineralogy and microbiology.

Light microscope is able to send light. Light is being focused in a tight breath whereby that light passes through a sample which later it is able to create an image. This image passes to different lenses which magnifies it until it reaches the camera.

There are different types of microscope for example, Compound light microscope, Simple light microscope, and monocular microscope.

In simple light microscope only one lens which which is being used to magnify an object and it is not able to reach to a higher magnification.

In compound light microscope it uses two lenses to produce image. For example eyepiece lens and objective lens.

Explanation:

The British Petroleum (bp's) effort to close the blowout preventer and install a containment dome following an explosion on the deepwater horizon drilling rig is an example of regulatory policy change.

The deepwater horizon drilling rig is a semi-submersible, transportable, floating, flexibly oriented drilling rig that could work in sea depths of up to 10,000 feet which is approximately 3,000 meters.

During the explosion that occurred in April 2010, British Petroleum made several efforts to contain the damages made and to prevent further outbreaks of disasters.

Part of the changes was shifting from a blowout preventer that has a specialized valve to seal, manage, and monitor oil and gas wells in order to prevent blowouts to a containment dome (a crucial component of a system meant to control an oil well's underwater blowout).

Therefore, we can conclude that the British Petroleum (bp's) effort to close the blowout preventer and install a containment dome following an explosion on the deepwater horizon drilling rig is an example of regulatory policy change.

Learn more about deepwater horizon drilling rig here:

https://brainly.com/question/21103915?referrer=searchResults

Answer:A

Explanation:

Answer:

who lives in Barclays what?? this makes no sense

Explanation

Answer:

QP

Explanation:

P has 9 electrons.

Electronic Configuration : 2, 7

Valence electrons : 7

P needs 1 electron to get stable electronic configuration.

Q has 3 electrons.

Electronic Configuration : 2, 1

Valence electrons : 1

P needs to loose 1 electron to get stable electronic configuration.

Q donates 1 electron,

Q -----> Q+ + 1 e-

P gains 1 electron,

P + 1 e- -----> P-

Q+ + P- -----> QP

This is an ionic compound.

Answer:

B. Drink Mix

Explanation:

Assuming the drink mix is something like Kool-aid, it is soluble in water. The rest are solids that cannot be dissolved in water.

Answer:

here is your answer.

Explanation:

atom.

thanks for asking:)

Deep ocean trenches, volcanoes, island arcs, submarine mountain ranges, and fault lines are examples of features that can form along plate tectonic boundaries.Because of the plates there are many things that is being made with the plates, but without the plates that makes earthquakes there wouldn't be any mountains,volcanoes, islands, fault lines, etc.For example, the San Andreas Fault couldn't have been made if it weren't for the plates.

Hope this helps! =D

Answer:

The answer to your question is Basic

Explanation:

pH ranges from 0 to 14, with 7 being neutral. pHs less than 7 are acidic while pHs greater than 7 are alkaline (basic).

I hope this helps!

Answer:A, Both reactivity and electronegativity decrease down a group.

Explanation: As you go down the periodic table they both will decrease

The rate of diffusion change would increase if the PO₂ in the capillaries was 40 mmHg and the PO₂ in the muscle cell changed from 40 to 20 mmHg.

Simple diffusion is the movement of molecular substances from a region of higher concentration to lower concentration. The mechanism with which the movement of O₂ travels from the blood to the body tissues takes place with the use of simple diffusion.

Now, if PO₂ changes from 40 → 20 mmHg in the muscle cells, and the PO₂ in the blood = 40mmHg. It implies that the pressure gradient(P) has increased. As such, there is an increase in the rate of diffusion of oxygen from the blood to muscle cells.

Learn more about diffusion here:

https://brainly.com/question/14392880?referrer=searchResults

Answer:

it dissolves or disintegrates

Explanation: