PLZ HELP! An electron moved from a lower energy level to a higher energy level. What most likely happened during the transition?

What is the molarity of a solution composed

Neporo4naja [7]

Answer:

0.0845 M

Explanation:

First we <u>convert 4.27 grams of potassium iodide into moles</u>, using its <em>molar mass</em>:

Molar Mass of KI = 166 g/mol

4.27 g ÷ 166 g/mol = 0.0257 mol

Now we <u>calculate the molarity of the solution</u>, using <em>the number of moles and the given volume</em>:

Molarity = moles / liters

Molarity = 0.0257 mol / 0.304 L = 0.0845 M

7 0

3 years ago

Calculate the Molarity when a 6.11 mL solution of 0.1 H2SO4 is diluted with 105.12 mL of water

barxatty [35]

Molarity after dilution : 0.0058 M

<h3>Further explanation </h3>

The number of moles before and after dilution is the same

The dilution formula

M₁V₁=M₂V₂

M₁ = Molarity of the solution before dilution

V₁ = volume of the solution before dilution

M₂ = Molarity of the solution after dilution

V₂ = Molarity volume of the solution after dilution

M₁=0.1 M

V₁=6.11

V₂=105.12

$\tt M_2=\dfrac{M_1.V_1}{V_2}=\dfrac{0.1\times 6.11}{105.12}=0.0058~M$

5 0

3 years ago

Do plasmids have an importance beyond the practice of genetic engineering?

kozerog [31]

Answer: Yes

Explanation: Plasmids offer a number of unique characteristics that make genetic engineering much more efficient. Plasmids are a type of non-chromosomal DNA. Integrating DNA into a bacterial or other chromosome is far more complex than simply putting DNA into a cell; plasmids make it easier to transport DNA into a cell by eliminating this step.

4 0

2 years ago

Please help with the attached picture question 21, 22, 23

klasskru [66]

Explanation:

21. The given molecule for cracking is tetradecane.

On cracking it forms one mole of decane (C10H22) and two moles of ethene gas.

The chemical equation is shown below:

$C_1_4H_3_0->C_1_0H_2_2+2C_2H_4$

22. The essential condition for the formation of an ester is the reaction of alcohol and acid in presence of concentrated sulfuric acid.

Thus among the given options, the first option is the correct one.

23. Isomers of butanol are shown below:

It is 2-butanol.

The position of -OH group changes to the second carbon.

5 0

3 years ago

Nitrogen and hydrogen combine to form ammonia in the Haber process. Calculate (in kJ) the standard enthalpy change ∆H° for the r

Kazeer [188]

Answer:

∆H° rxn = - 93 kJ

Explanation:

Recall that a change in standard in enthalpy, ∆H°, can be calculated from the inventory of the energies, H, of the bonds broken minus bonds formed (H according to Hess Law.

We need to find in an appropiate reference table the bond energies for all the species in the reactions and then compute the result.

N₂ (g) + 3H₂ (g) ⇒ 2NH₃ (g)

1 N≡N = 1(945 kJ/mol) 3 H-H = 3 (432 kJ/mol) 6 N-H = 6 ( 389 kJ/mol)

∆H° rxn = ∑ H bonds broken - ∑ H bonds formed

∆H° rxn = [ 1(945 kJ) + 3 (432 kJ) ] - [ 6 (389 k J]

∆H° rxn = 2,241 kJ -2334 kJ = -93 kJ

be careful when reading values from the reference table since you will find listed N-N bond energy (single bond), but we have instead a triple bond, N≡N, we have to use this one .

8 0

3 years ago