What is the molar mass of NaCl (table salt)?

What mass of Fe(OH)3 is produced when 35 mL of 0.250 M Fe(NO3)3 solution is mixed with 55 mL of a 0.180 M

Zina [86]

Answer:

0.35 g.

Explanation:

We'll begin by calculating the number of mole of Fe(NO3)3 in 35 mL of 0.250 M Fe(NO3)3 solution.

This is illustrated below:

Molarity of Fe(NO3)3 = 0.250 M

Volume = 35 mL = 35/1000 = 0.035 L

Mole of Fe(NO3)3 =?

Molarity = mole /Volume

0.250 = mole of Fe(NO3)3 / 0.035

Cross multiply

Mole of Fe(NO3)3 = 0.25 x 0.035

Mole of Fe(NO3)3 = 8.75×10¯³ mole

Next, we shall determine the number of mole of KOH in 55 mL of 0.180 M

KOH solution. This is illustrated below:

Molarity of KOH = 0.180 M

Volume = 55 mL = 55/1000 = 0.055 L

Mole of KOH =.?

Molarity = mole /Volume

0.180 = mole of KOH /0.055

Cross multiply

Mole of KOH = 0.180 x 0.055

Mole of KOH = 9.9×10¯³ mole.

Next, we shall write the balanced equation for the reaction. This is given below:

3KOH + Fe(NO3)3 —> Fe(OH)3 + 3KNO3

From the balanced equation above,

3 moles of KOH reacted with 1 mole of Fe(NO3)3 to produce 1 mole of Fe(OH)3.

Next, we shall determine the limiting reactant. This can be obtained as follow:

From the balanced equation above,

3 moles of KOH reacted with 1 mole of Fe(NO3)3.

Therefore, 9.9×10¯³ mole of KOH will react with = (9.9×10¯³ x 1)/3 = 3.3×10¯³ mole of Fe(NO3)3.

From the above illustration, we can see that only 3.3×10¯³ mole out of 8.75×10¯³ mole of Fe(NO3)3 given is needed to react completely with 9.9×10¯³ mole of KOH.

Therefore, KOH is the limiting reactant and Fe(NO3)3 is the excess reactant.

Next, we shall determine the number of mole of Fe(OH)3 produced from the reaction.

In this case, we shall use the limiting reactant because it will give the maximum yield of Fe(OH)3 as all of it is consumed in the reaction.

The limiting reactant is KOH and the mole of Fe(OH)3 produce can be obtained as follow:

From the balanced equation above,

3 moles of KOH reacted to produce 1 mole of Fe(OH)3.

Therefore, 9.9×10¯³ mole of KOH will react to produce = (9.9×10¯³ x 1)/3 = 3.3×10¯³ mole of Fe(OH)3.

Finally, we shall convert 3.3×10¯³ mole of Fe(OH)3 to grams. This can be obtained as follow:

Molar mass of Fe(OH)3 = 56 + 3(16 + 1) = 56 + 3(17) = 107 g/mol

Mole of Fe(OH)3 = 3.3×10¯³ mole

Mass of Fe(OH)3 =?

Mole = mass /Molar mass

3.3×10¯³ = Mass of Fe(OH)3 / 107

Cross multiply

Mass of Fe(OH)3 = 3.3×10¯³ x 107

Mass of Fe(OH)3 = 0.3531 ≈ 0.35 g.

Therefore, 0.35 g of Fe(OH)3 was produced from the reaction.

8 0

3 years ago

Suppose you need to prepare 141.9 mL of a 0.223 M aqueous solution of NaCl. What mass of NaCl do you need to use to make the sol

Afina-wow [57]

Answer:

1.811 g

Explanation:

The computation of the mass need to use to make the solution is shown below:

We know that molarity is

$Molarity = \frac{Number\ of\ moles}{Volume\ in\ L}$

So,

$Number\ of\ moles = Molarity\ \times Volume\ in\ L$

$= 0.223\times 0.141$

= 0.031 moles

Now

$Mass = moles \times Molecualr\ weight$

where,

The Molecular weight of NaCl is 58.44 g/mole

And, the moles are 0.031 moles

So, the mass of NaCL is

$= 0.031 \times 58.44$

= 1.811 g

We simply applied the above formulas

3 0

3 years ago

Here's the question ~

Lelechka [254]

Using the Rydberg formula, the spectral line of H - atom is suitable for this purpose is Paschen, ∞ → 3.

Using the Rydberg formula;

1/λ = RH(1/nf^2 - 1/ni^2)

Given that;

λ = wavelength

RH = Rydberg constant

nf = final state

ni = initial state

When final state = 3 and initial state = ∞

Then;

1/λ = 1 × 10^7 m-1 (1/3^2 - 1/ ∞^2)

1/λ = 1 × 10^7 m-1 (1/3^2 )

λ = 900 nm

Hence, the correct answer is Paschen, ∞ → 3

Learn more about the Rydberg formula; brainly.com/question/17753747

3 0

2 years ago

Read 2 more answers

Students in science are studying solutions and the dissolving rate of solids. One group was given some instant lemonade mix to

UkoKoshka [18]

Answer: A E D C

Explanation:

7 0

3 years ago

Do you think thermal expansion affects all states of matter or just the solid? Explain your thinking.

torisob [31]

Answer:

All three states of matter (solid, liquid and gas) expand when heated. The atoms themselves do not expand, but the volume they take up does.

When a solid is heated, its atoms vibrate faster about their fixed points. The relative increase in the size of solids when heated is therefore small. Metal railway tracks have small gaps so that when the sun heats them, the tracks expand into these gaps and don’t buckle.

Liquids expand for the same reason, but because the bonds between separate molecules are usually less tight they expand more than solids. This is the principle behind liquid-in-glass thermometers. An increase in temperature results in the expansion of the liquid which means it rises up the glass.

Molecules within gases are further apart and weakly attracted to each other. Heat causes the molecules to move faster, (heat energy is converted to kinetic energy) which means that the volume of a gas increases more than the volume of a solid or liquid.

However, gases that are contained in a fixed volume cannot expand - and so increases in temperature result in increases in pressure.:

5 0

3 years ago