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Name two metals alloyed with iron to make stainless steel.

kirill115 [55]

For stainless steel different kinds of compositions are used. Based on that different series of stainless steel has been coined.
1. Series 200 - Iron alloyed with chromium, nickel and manganese.
2. Series 300 - It has
a. Stainless Steel 304 - it has composition of 18% chromium and 8% Nickel
b. Stainless Steel 316 - This has 18% chromium and 10% Nickel

Each kind of stainless steel is of different cost and has different applications.

7 0

2 years ago

7. An element's most stable ion forms an ionic compound with chlorine having the formula XCl2. If the ion of element X has a mas

Serhud [2]

Answer:

The element is strontium and the number of neutrons it have is 51.

Explanation:

Based on the given information, the ionic compound is,

XCl₂ ⇔ X₂⁺ + 2Cl⁻

X2+ is the ion of the mentioned element

As mentioned in the given question, the number of electrons of the element X is 36 and as seen from the reaction the charge present on the ion is +2. Now the atomic number will be,

No. of electrons = atomic number - charge

36 = atomic number - 2

Atomic number = 38

Based on the periodic table, the atomic number 38 is for strontium element, and the sign of strontium is Sr. Hence, the element X is Sr.

Now based on the given information, the mass number of the element is 89. Now the no. of neutrons will be,

No. of neutrons = mass number - atomic number

= 89 - 38

= 51 neutrons.

4 0

3 years ago

If the energy of the reactants is less than

expeople1 [14]

The opposite type of reaction (where energy is taken in from the surroundings of a reaction and thus the energy of the reactants is lower than that of the products) is called an endothermic reaction

7 0

2 years ago

2 of 20 Which intermolecular force or bond is primarily responsible for the solubility of CH3OH in water? lonic bonding Hydrogen

Vlad [161]

Answer:

Hydrogen bonding

Explanation:

As a rule of thumb, "likes dissolve like", meaning polar solutes dissolve in polar solvents and nonpolar solutes in nonpolar solvents. In this case, water is polar (dipolar moment = 1.85 Debye) dissolves methanol which is also polar (dipolar moment = 1.69 Debye). Besides being dipoles, both molecules have atoms of Hydrogen with a covalent bond to more electronegative atoms of Oxygen. When this happens, stronger dipole-dipole interactions appear known as Hydrogen bonding. There is an electrostatic attraction between H (positive charge density) and O (negative charge density).

5 0

2 years ago

Which of the following processes are exothermic?Which of the following processes are exothermic?Br(g) + e- → Br-(g)Li(s) → Li(g)

Ksenya-84 [330]

Answer:

The correct answer is: None of the above are exothermic.

Explanation:

Energy is the ability to perform a job or to produce heat. Chemical reactions involve a rearrangement of atoms between substances with rupture or formation of chemical bonds and this generates changes in the energy of the system.

An exothermic reaction is that reaction where heat is released. This means that the energy of the molecules of the products is less than the energy of the molecules of the reactants.

An endothermic reaction is that chemical reaction that, when it occurs, consumes energy, that is, the products obtained have greater energy than the initial reagents, since they have taken part of the heat of the environment.

Sublimation is the change of state of a substance from solid to gas directly without going through the liquid state. This process requires energy to be carried out because the strong attractive energies between the solid molecules must be broken. So it is an endothermic process. This is what happens in the following reactions:

Li(s) → Li(g)

NaF(s) → Na+(g) + F-(g)

Dissociation is a process in which complexes, molecules or salts are separated into smaller molecules, ions or radicals, usually reversibly. Within the dissociation is the homolytic rupture, where each atom separates and carries the same charge of electrons. Thus free radicals are formed. To dissociate or break these bonds requires energy, so it is endothermic. This type of reaction occurs in:

Cl2(g) → 2Cl(g)

Electronic affinity is defined as the energy exchanged when an isolated and fundamental state gaseous atom takes an electron to form an anion (negative ion). When the electronic affinity is greater than zero, the process would be endothermic and when the electroaffinity is less than zero, the process would be exothermic.

This occurs in:

Br(g) + e- → Br-(g)

The highest electronic affinities are for the elements of group 17 of the periodic table, the group to which bromine belongs. This means that the electronic affinity is greater than zero and is endothermic.

The correct answer is: None of the above are exothermic.

Br(g) + e- → Br-(g) 

7 0

3 years ago

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