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Stella [2.4K]
2 years ago
14

A theory is:

Chemistry
1 answer:
SpyIntel [72]2 years ago
3 0
A theory is a proposed explanation for an observation
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What are the principal alloy elements of an AISI 4340 steel? How much carbon does it have? Is it hardenable? By what techniques?
amid [387]

Answer:

The principal elements are Iron, Nickel, Chromium

It has 0.37% to 0.43% Carbon

It is hardenable.

It can be hardened by cold working, annealing, quenching.

Explanation:

A)

The chemical composition of AISI 4340 Steel are as follows:

Iron  ---  95% to 96%

Nickel  ---  1.6% to 2.0%

Chromium  ---  0.7% to 0.9%

Manganese  ---  0.6% to 0.8%

Carbon  ---  0.37% to 0.43%

Molybdenum  ---  0.2% to 0.3%

Silicon  ---  0.15% to 0.30%

Sulfur  ---   0.040%

Phosphorous  --- 0.0350%

So, the principal alloy elements from this composition are <u>Iron, Nickel and Chromium</u>

B)

The carbon content in this alloy is <u>0.37% to 0.43%</u>

C)

<u>Yes, it can be hardened</u>.

D)

<u>It can be Hardened by Cold Working, Annealing or Quenching</u>.

3 0
3 years ago
If the half-life of technitium-104 is 18.0 min, how much of a 14.2-g sample will remain after 72 minutes?
Debora [2.8K]
The decay of a radioactive isotope can be predicted using the formula: A = Ao[2^(-t/T_0.5)] where A is the amount after time t, Ao is the original amount and T_0.5 is the half-life. Using the equation and the given values, 0.888 g of the sample will remain after 72 minutes. 
3 0
3 years ago
Read 2 more answers
Match each part of the electrochemical cell with its function.
umka21 [38]

Hi!


The correct options would be:

1. Cathode - <em>reduction</em>

The cathode is the negatively charged electrode, and so has an excess of electrons. Cations (positively charged ions) are attracted to the cathode, and gain electrons to acquire a neutral charge. The process in which a gain of electron occurs is called reduction.


2. Anode - <em>oxidation</em>

The opposite occurs at the anode which is positively charged and attracts negatively charged ions, anions. These anions lose their electrons at the anode to acquire a neutral charge, and the process involving loss of electrons is known as oxidation.


3. Salt Bridge - <em>ion transport </em>

Salt bridge is a physical connection between the the anodic and cathodic half cells in an electrochemical cell and is a pathway that facilitates the flow of ions back and forth these half cells. Salt bridge is involved in maintaining a neutral condition in the electrochemical cells, and its absence would result in the accumulation of positive charge in the anodic cell, and negative charge in the cathodic cell.


4. Wire - <em>electron transport </em>

Wires have a universal role of being a pathway for the transport of electrons in circuit. This role is also the same in the wires involved in an electrochemical cells where they are used to transport electrons from the anodic half cell, and this electron transport results in the generation of electricity in the internal circuit of the electrochemical cell.


Hope this helps!

4 0
3 years ago
Wine goes bad soon after opening because the ethanol (CH3CH2OH) dissolved in it reacts with oxygen (O2) gas to form water and aq
andrezito [222]

The number of mole of oxygen needed is of 0.080 mole.

To solve this question, we'll begin by writing the balanced equation for the reaction. This is illustrated below:

<h3>CH₃COOH + 2O₂ —> CO₂ + 2H₂O</h3>

From the balanced equation above,

2 moles of O₂ reacted to produce 2 moles of H₂O.

Finally, we shall determine the number of mole of O₂ needed to produce 0.080 mole of H₂O. This can be obtained as follow:

From the balanced equation above,

2 moles of O₂ reacted to produce 2 moles of H₂O.

Therefore,

0.080 mole of O₂ will also react to produce 0.080 mole of H₂O.

Thus, 0.080 mole of oxygen, O₂, is needed for the reaction.

Learn more: brainly.com/question/1563415

7 0
3 years ago
What is the minimum amount of heat required to completely melt 40.0 grams of ice at its melting point?
elena55 [62]
If 20.0 grams of ice takes about 6680j...then 40.0 grams of ice would take ___ .
6 0
3 years ago
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