What is the process whereby stars create elements heavier than hydrogen?

g 304 mL of a 0.36 M potassium hydroxide solution is added to 341 mL of a 0.51 M lithium hydroxide solution. Calculate the pOH o

Liono4ka [1.6K]

Answer:

pOH = 0.36

Explanation:

Both potassium hydroxide and lithium hydroxide solutions are strong bases, so you assume 100% dissociation.

1. Potassium hydroxide solution, KOH

Volume, V = 304 mL = 0.304 liter

Molarity, M = 0.36 M

number of moles, n = M × V = 0.36M × 0.304 liter = 0.10944 mol

1 mole of KOH produces 1 mol of OH⁻ ion, thus the number of moles of OH⁻ is 0.10944

2. LIthium hydroxide, LiOH

Volume, V = 341 mL = 0.341 liter

Molarity, M = 0.51 M

number of moles, n = M × V = 0.341 liter × 0.51 M = 0.17391 mol

1mole of LiOH produces 1 mol of OH⁻ ion, thus the number of moles of OH⁻ is 0.17391

3. Resulting solution

Number of moles of OH⁻ ions = 0.10944 mol + 0.17391 mol = 0.28335 mol

Volume of solution = 0.304 liter + 0.341 liter = 0.645 liter

Molar concentration = 0.28335 mol / 0.645 liter = 0.4393 M

4. pOH

$pOH=-\log [OH^-]=-\log (0.439)=0.36$ ← answer

5 0

3 years ago

Indicate the SI base units or derived units that are appropriate for the following measurements:

Alisiya [41]

Answer:

The units of SI: meter, kilogram, second, Kelvin

Explanation:

(a) The length of a marathon race: meter (m)

(b) The mass of an automobile : kilogram (kg)

(c) The volume of a swimming pool : cubic meter (m^3)

(d) The speed of an airplane : (m/s)

(e) The density of gold : (kg/m^3)

(f) The area of a football field : square meter (m^2)

(g) The maximum temperature at the South Pole on April 1,1913: Kelvin (K)

7 0

3 years ago

Which subatomic particles are located in the nucleus of a ca-40 atom?

san4es73 [151]

Answer:

3) neutrons and protons

Explanation:

I just completed Grade 11 Chemistry with a 97% and I'm still under the impression that all atoms have only neutrons and protons in their nuclui.

I apologize if this is a question above my current education.

3 0

3 years ago

What is the percentage of water in the hydrate CoCl2 • 6H2O? Show your work.

Lelu [443]

Hello!

First you have to find the molar mass of the molecules

C = 12
O = 16
2Cl = 71
6H2O = 108

Add them up to find the total molar mass

12 + 16 + 71 + 108 = 207g/mol

Divide the amount of water by the total molar mass

108 / 207 = 0.5217

Convert this to a decimal

0.5217 = 52.17%

The answer is 52.17%

Hope this helps!

7 0

4 years ago

What is the density of an object that has a mass of 149. 8 g and displaces 12. 1 ml of water when placed in a graduated cylinder

kozerog [31]

Answer:

Explanation:

The density of a substance can be found by using the formula

$d = \frac{m}{v} \\$

m is the mass

v is the volume

From the question

m = 149.8 g

v = 12.1 mL

We have

$d = \frac{149.8}{12.1} = 12.380165... \\$

We have the final answer as

Hope this helps you

4 0

2 years ago