Which of the following elements has the highest electronegativity?

A)Completaţi ecuaţiile chimice următoare cu formulele chimice şi coeficienţii adecvaţi:

Scilla [17]

Answer:co2

Explanation:because of the oxygen levels

6 0

3 years ago

What are the challenges for a "sustainable" world of lithium ion batteries?

Neporo4naja [7]

The Lithium-ion Battery Problem

Overheating. They overheat and explode if charged too fast.

Short life time. They die after less than 1,000 charge/discharge cycles.

Flammable. They use chemicals that are flammable. ...

Toxic. ...

Underperform in extreme temperatures. ...

Expensive casing. ...

Expensive to transport.

7 0

2 years ago

You mix 285.0 mL of 1.20 M lead(II) nitrate with 300.0 mL of 1.60 M potassium iodide. The lead(II) iodide is insoluble. Which of

SIZIF [17.4K]

Answer:

D. The final concentration of NO3– is 0.821 M.

Explanation:

Considering:

$Molarity=\frac{Moles\ of\ solute}{Volume\ of\ the\ solution}$

Or,

$Moles =Molarity \times {Volume\ of\ the\ solution}$

Given :

For potassium iodide :

Molarity = 1.60 M

Volume = 300.0 mL

The conversion of mL to L is shown below:

1 mL = 10⁻³ L

Thus, volume = 300.0×10⁻³ L

Thus, moles of potassium iodide :

$Moles=1.60 \times {300.0\times 10^{-3}}\ moles$

Moles of potassium iodide = 0.48 moles

For lead(II) nitrate :

Molarity = 1.20 M

Volume = 285 mL

The conversion of mL to L is shown below:

1 mL = 10⁻³ L

Thus, volume = 285×10⁻³ L

Thus, moles of lead(II) nitrate :

$Moles=1.20\times {285\times 10^{-3}}\ moles$

Moles of lead(II) nitrate = 0.342 moles

According to the given reaction:

$2KI_{(aq)}+Pb(NO_3)_2_{(aq)}\rightarrow PbI_2_{(s)}+2KNO_3_{(aq)}$

2 moles of potassium iodide react with 1 mole of lead(II) nitrate

1 mole of potassium iodide react with 1/2 mole of lead(II) nitrate

0.48 moles potassium iodide react with 0.48/2 mole of lead(II) nitrate

Moles of lead(II) nitrate = 0.24 moles

Available moles of lead(II) nitrate = 0.342 moles

Limiting reagent is the one which is present in small amount. Thus, potassium iodide is limiting reagent.

Also, consumed lead(II) nitrate = 0.24 moles (lead ions precipitate with iodide ions)

Left over moles = 0.342 - 0.24 moles = 0.102 moles

Total volume = 300 + 285 mL = 585 mL = 0.585 L

So, Concentration = 0.102/0.585 M = 1.174 M

Statement A is correct.

The formation of the product is governed by the limiting reagent. So,

2 moles of potassium iodide gives 1 mole of lead(II) iodide

1 mole of potassium iodide gives 1/2 mole of lead(II) iodide

0.48 mole of potassium iodide gives 0.48/2 mole of lead(II) iodide

Mole of lead(II) iodide = 0.24 moles

Molar mass of lead(II) iodide = 461.01 g/mol

Mass of lead(II) chloride = Moles × Molar mass = 0.24 × 461.01 g = 111 g

Statement B is correct.

Potassium iodide is the limiting reagent. So all the potassium ion is with potassium nitrate . Thus,

2 moles of Potassium iodide on reaction forms 2 moles of potassium ion

0.48 moles of Potassium iodide on reaction forms 0.48 moles of potassium ion

Total volume = 300 + 285 mL = 585 mL = 0.585 L

So, Concentration = 0.48/0.585 M = 0.821 M

Statement C is correct.

Nitrate ions are furnished by lead(II) nitrate . So,

1 mole of lead(II) nitrate produces 2 moles of nitrate ions

0.342 mole of lead(II) nitrate produces 2*0.342 moles of nitrate ions

Moles of nitrate ions = 0.684 moles

So, Concentration = 0.684/0.585 M = 1.169 M

Statement D is incorrect.

4 0

3 years ago

Describe the composition of humus and why it is an effective organic fertilizer.

asambeis [7]

Answer:

Humus, which ranges in colour from brown to black, consists of about 60 percent carbon, 6 percent nitrogen, and smaller amounts of phosphorus and sulfur. As humus decomposes, its components are changed into forms usable by plants.

samira-

5 0

2 years ago

A naoh (aq) stock solution was created by dissolving 3.88 g naoh in water to create a 100.00 ml solution. what is the concentrat

Bess [88]

0.0381g/mL will be concentration of this solution

The ratio of a solute—a substance that dissolves—to a solvent—a substance that does not dissolve—determines the concentration of a solution in chemistry. C = m/V, where C is the concentration, m is the mass of the solute dissolved, and V is the overall volume of the solution, is the accepted formula.

How to reach the solution?

First find for the density of NaOh which is 2.13 g/cm3

3.88 ÷ 2.13 = 1.82mL

100mL + 1.82mL = 101.82mL

3.88 ÷ 101.82mL = 0.0381g/mL

More about NaOh:

The extremely adaptable chemical sodium hydroxide (NaOH), sometimes referred to as caustic soda or lye, is employed in a range of manufacturing processes. A byproduct of the manufacturing of chlorine is sodium hydroxide. Numerous items that are used on a daily basis, including paper, metal, drain and oven cleansers for industry, soap, and detergents, are made with sodium hydroxide.

Learn more about Naoh here:

brainly.com/question/3366922

#SPJ4

5 0

1 year ago