All categories

3 years ago

What basic law of chemical reactions do nuclear reactions break

1 answer:

4 0

The law conservation of mass, because part of the mass can be converted into energy
also, the elements are changing during nuclear reactions, new elements are formed

You might be interested in

What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = pKa? Ka = 1.8×10-5

Westkost [7]

Answer:

a) We have to add 0.9 mole NaOH to 1.0 L of 1.8 M HC2H3O2

b) We have to add 0.277 mole NaOH to 1.0 L of 1.8 M HC2H3O2

c) We have to add 1.16 mole NaOH to 1.0 L of 1.8 M HC2H3O2

Explanation:

a) <em>What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = pKa?</em>

<em />

Step 1: Data given

Volume of HC2H3O2 = 1.0 L

Molarity of HC2H3O2 = 1.8 M

Ka = 1.8*10^-5

ph = pK = -log(1.8*10^-5) = 4.74

Step 2:

Use the Henderson-Hasselbalch equation.

pH = pKa + log(A-/HA)

4.74 = 4.74 + log(A-/HA)

0 = log(A-/HA)

A-/HA = 1

Consider X = moles of NaOH added (and moles of A- formed)

Remaining moles of HA = 1.8 - X

moles of A- = X

HA = 1.8 - X

X/(1.8-X) = 1

X =0.9

To control we can do the following equation:

4.74 = 4.74 + log(0.9/0.9) = 4.74

b)<em> What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = 4.00?</em>

Step 1: Data given

Volume of HC2H3O2 = 1.0 L

Molarity of HC2H3O2 = 1.8 M

Ka = 1.8*10^-5

ph = 4

Step 2:

Use the Henderson-Hasselbalch equation.

pH = pKa + log(A-/HA)

4 = 4.74 + log(A-/HA)

-0.74 = log(A-/HA)

A-/HA = 0.182

Consider X = moles of NaOH added (and moles of A- formed)

Remaining moles of HA = 1.8 - X

moles of A- = X

HA = 1.8 - X

X/(1.8-X) = 0.182

X =0.277

To control we can do the following equation:

4 = 4.74 + log(0.277/1.523)

<em>c) What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = 5.00</em>

Step 1: Data given

Volume of HC2H3O2 = 1.0 L

Molarity of HC2H3O2 = 1.8 M

Ka = 1.8*10^-5

ph = 5

Step 2:

Use the Henderson-Hasselbalch equation.

pH = pKa + log(A-/HA)

5 = 4.74 + log(A-/HA)

0.26 = log(A-/HA)

A-/HA = 1.82

Consider X = moles of NaOH added (and moles of A- formed)

Remaining moles of HA = 1.8 - X

moles of A- = X

HA = 1.8 - X

X/(1.8-X) = 1.82

X =1.16

To control we can do the following equation:

5 = 4.74 + log(1.16/0.64) = 5

3 0

4 years ago

How many elements are identified in tearms of their atoms

lianna [129]

<span>their identified by the number of protons they have in the nucleus which = their electrons. </span>

6 0

4 years ago

a radioactive nuclide that is used for geological dating has an atomic number of 19 and mass 40. what is the symbol of this nucl

PIT_PIT [208]

The symbol of the radioactive nuclide, given the data is ⁴⁰₁₉K

<h3>Data obtained from the question</h3>

Atomic number = 19
Mass number = 40
Symbol of nuclide =?

<h3>How to determine the nuclide</h3>

From the question given above, the atomic number of the nuclide is 19.

Comparing the atomic number (i.e 19) of the nuclide with those in the periodic table, the nuclide is potassium with a symbol of K

<h3>How to determine the symbol of the nuclide</h3>

Atomic number (Z) = 19
Mass number (A) = 40
Name of nuclide = Potassium (K)
Symbol of nuclide =?

The symbol of a nuclide is given as ᴬ₂X

Where

A is the mass number
Z is the atomic number
X is the symbol of the element

Thus,

ᴬ₂X => ⁴⁰₁₉K

Therefore, the symbol of the nuclide is ⁴⁰₁₉K

Learn more about composition of atoms:

brainly.com/question/886387

#SPJ1

3 0

2 years ago

The reaction can be described using the equation: 2C2H25O24CO22H2O. How much C2H2is needed to react with 68.1 g of O2to produce

Sophie [7]

Answer:

22.13g

Explanation:

We'll begin by writing a balanced equation for the reaction. This is illustrated below:

2C2H2 + 5O2 —> 4CO2 + 2H2O

Next, we'll calculate the mass of C2H2 and O2 that reacted from the balanced equation. This is illustrated below:

Molar Mass of C2H2 = (12x2) + (2x1)

= 24 + 2 = 26g/mol

Mass of C2H2 that reacted from the balanced equation = 2 x 26 = 52g

Molar Mass of O2 = 16x2 = 32g/mol

Mass of O2 that reacted from the balanced equation = 5 x 32 = 160g

Now, we can obtain the mass of C2H2 that will react with 68.1g of O2 as follow:

From the balanced equation above,

52g of C2H2 reacted with 160g of O2.

Therefore, Xg of C2H2 will react with 68.1g of O2 i.e

Xg of C2H2 = (52x68.1)/160

Xg of C2H2 = 22.13g

Therefore, 22.13g of C2H2 is needed to react with 68.1g of O2

8 0

3 years ago

Titrations provide a method of quantitatively measuring the concentration of an unknown solution.

jekas [21]

Answer: True

Explanation:

Titration is a quantitative technique where a solution of known concentration is used to determine the concentration of an unknown solution. The titrant (the known solution) is added from a burette to a known quantity of the the unknown solution until the reaction is complete.

By knowing the volume of titrant, we can determine the concentration of the unknown.

Thus the statement Titrations provide a method of quantitatively measuring the concentration of an unknown solution is True .

4 0

3 years ago