What is an unknown element´s that has 35 protons

Oxidation of ethanol plssss

faltersainse [42]

(Na2Cr2O7) all the numbers are bellow not over

3 0

3 years ago

A 251 ml sample of 0.45M HCl is added to 455 mL of distilled water. What is the molarity of the

Oksi-84 [34.3K]

<u>We are given:</u>

251 mL sample of 0.45M HCl added to 455 mL distilled water

<u>Whack a mole! (finding the number of moles):</u>

We know that in order to find molarity, we use the formula:

Molarity = number of moles / Volume (in L)

so, number of moles is:

Number of moles = Molarity * Volume(in L)

now let's plug the values for the HCl solution to find the number of moles

Number of moles = 0.45M * 0.251 L

Number of moles = 0.113 moles

<u>Time to concentrate (finding the final concentration):</u>

Total final volume = 251 mL + 455 mL = 706 mL = 0.706 L

Number of moles of HCl = 0.113 moles

Molarity = Number of moles / Volume (in L)

Molarity = 0.113 / 0.706

Molarity = 0.16 M

___________________________________________________________

<u>BONUS METHOD TIME!!!</u>

We know the relation:

M1 * V1 = M2 * V2

where M1 and M2 are the initial and final molarities and V1 and V2 are initial and final volumes respectively

notice that I didn't mention that the volume has to be in Liters, that's because of the units being concerned with both sides of the equation, say I have the volume in mL and want to convert both these volumes to L, I would divide both sides by 1000, which would NOT change the overall value

Now, plugging values in this equation

(0.45) * (251) = (251 + 455)* (M2)

112.95 = (706)(M2)

M2 = 112.97/706 [dividing both sides by 706]

M2 = 0.16 Molar

8 0

3 years ago

Pleaseeeeeefgghhbbbbbbbbbb

ehidna [41]

<h2>Hey There!</h2><h2>_____________________________________</h2><h2>Answer:</h2><h2>----------------------------------------------------------------------</h2><h2>ELECTROPLATING </h2>

Electroplating the plating one metal on to the another metal, It is mostly used for preventing corrosion by using copper or chromium or decorate the object by using gold or silver plating.

__________________________________________________________

<h3>Principle:</h3>

When electricity is passed the thin layer of metal is deposited on another metal and water molecule given out as a By-Product, Thus this process works on the principle of Hydrolysis.

<h2>_____________________________________</h2><h2>QUESTION:</h2>

A) Electrolysis

B) Chromium prevents corrosion and gives the fine shining touch to the objects.

C) The metal which is deposited to the object i.e. spoon will be connected to the positive electrode of a battery, Thus it is anode. The spoon at which electroplating is need to be done is connected to the negative electrode, thus the Spoon is cathode.

<h2>_____________________________________</h2><h2>Best Regards,</h2><h2>'Borz'</h2>

5 0

3 years ago

What is the definition of critical thinking from the book ?

Naily [24]

Answer:

Critical thinking is the intellectually disciplined process of actively and skillfully conceptualizing, applying, analyzing.

Explanation:

3 0

3 years ago

[HELP PLEASE] Describe the difference between the ways valence electrons are rearranged when forming ionic bonds and covalent bo

nydimaria [60]

Answer:

Ionic bonding is the complete transfer of valence electron(s) between atoms. It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.

Explanation:

5 0

3 years ago