All categories

15 days ago

A mixture of KCl and KNO3

2 answers:

8 0

The percentage of KCl present in the mixture is approximately <span>40%</span><span>If we consider a 100-gram sample of the mixture:ω(K) = 44.20% ÷ 100% = 0.442.
m(K) = 0.442 · 100 g = 44.2 g.</span>n(K) = 44.2 g ÷ 39.1 g/mol.
n(K) = 1.13 mol.
n(KCl) + n(KNO₃) = n(K)
m(KCl) = x.
m(KNO₃) = y.
Two equations:
1) x + y = 100 g.
2) m(KCl)/M(KCl) + m(KNO₃)/M(KNO₃) = 1.13 mol.
x/74.55 g/mol + y/101.1 g/mol = 1.13 mol.
From the first equation, we find x = 100 - y and substitute into the second equation:
(100 - y)/74.55 + y/101.1 = 1.13 /×101.1.
135.61 - 1.356y + y = 114.24.
0.356y = 22.37 g.
y = 62.83 g.
Thus, x = m(KCl) = 100 g - 62.83 g = 37.17 g.

KiRa [2.8K]15 days ago

6 0

Answer:

The precise answer is option (a).

Explanation:

Assuming the total mass of the mixture is 100 g

let the mass of KCl be x

and the mass of

be y $KNO_3$

x + y = 100...(1)

Moles of KCl =

$\frac{x}{75.5 g/mol}$

Moles of K in KCl =

(1 mol is found in 1 mole of the compound) $\frac{x}{75.5 g/mol}$

Moles of

$KNO_3=\frac{y}{102 g/mol}$ in

(1 mol is contained in 1 mole of the compound) $KNO_3$ $\frac{y}{102 g/mol}$ The percentage of potassium in the mixture is 44.20 %

In a 100 g sample, the potassium mass = 44.20 g

Moles of potassium are

$\frac{44.20 g}{40 g/mol}=1.105 mol$ Thus,

..(2)

$\frac{x}{75.5 g/mol}+\frac{y}{102 g/mol}=1.105 mol$ By solving equations (1) and (2):

we obtain y = 63.78 g, x=36.22 g

Calculating the percentage of KCl:

$\frac{36.22 g}{100g}\times 100=36.22 g\%$

The percent of KCl in the mixture is approximately 40%. Therefore, option (a) is correct.

You might be interested in

If the tip of the syringe, "The Titrator", was not filled with NaOH before the initial volume reading was recorded, would the co

Anarel [2728]

Answer:

The trial's estimated concentration of acetic acid in the vinegar would be higher than the true concentration.

Detailed explanation:

"The titrator" holds the base solution (NaOH) that will be used to titrate the vinegar solution (acetic acid).

If we assume that the syringe tip was not primed prior to recording the initial volume, a portion of the base solution that is released will be retained in the tip of the syringe, resulting in the actual volume of base added to the acetic acid being less than calculated based on the readings.

Consequently, in the calculations, a larger volume of the base is used than what was genuinely applied, which leads to an inflated number of moles of base compared to the actual amount utilized.

Thus, at the point of neutralization, where the equivalents of base equal the equivalents of acid, you will report a higher amount of acid equivalents, resulting in a calculated concentration that is greater than the true concentration. This ultimately means the concentration of acetic acid in the vinegar of that trial would be greater than the actual concentration.

6 0

7 days ago

A food worker had safely cooled a large pot of soup to 70 F (21 C) with two hours. What temperature must the soup Reach in the f

lorasvet [2668]

After four hours of cooling, the soup reached a temperature of 140 F (or) 42 C.

Explanation:

A food worker allowed a cup of soup to cool for two hours,

step 1: The temperature attained in two hours is 70 F (or) 21 C

step 2: Consequently, in four hours, this doubles the value

Therefore, the temperature after four hours is 2(70)= 140 F (or) 2(21)= 42 C

4 0

1 month ago

Draw the best lewis structure for bro4- and determine the formal charge on bromine

Alekssandra [2891]

Answer:

The Lewis-dot structure: illustrates the connections between atoms within a molecule and indicates the unpaired electrons that are found in it. Dots are used to represent the electrons.

The molecule in question is the perbromate ion.

Bromine possesses '7' valence electrons, while oxygen has '6' valence electrons.

Thus, the overall count of valence electrons in the perbromate ion is $BrO_4^-$ = 7 + 4(6) + 1 = 32

Based on the Lewis-dot structure, there are 14 bonding electrons and 18 non-bonding electrons present.

The formula for determining formal charge:

$\text{Formal charge}=\text{Valence electrons}-\text{Non-bonding electrons}-\frac{\text{Bonding electrons}}{2}$

$\text{Formal charge on }Br=7-0-\frac{14}{2}=0$

Displayed below is the Lewis-dot structure of the perbromate ion.

7 0

22 days ago

Read 2 more answers

Upon heating with acid salicylic acid can form a polymer. what is its structure likely to be

KiRa [2853]

Refer to the attached image. This does not depict the polymerization reaction of salicylic acid. It merely illustrates the structure of salicylic acid and what it looks like post-polymerization. The polymerization occurs through the linking of salicylic acid molecules, resulting in the formation of one water molecule.

4 0

12 days ago

A 1.20 g sample of water is injected into an evacuated 5.00 l flask at 65°c. part of the water vaporizes and creates a pressure

alisha [2865]

Assuming the water vapor behaves as an ideal gas,

PV = nRT

For conversions, 760 mmHg = 101325 Pa and 1,000 L = 1 m³
(187.5 mmHg)(101325 Pa/760 mmHg)(5 L)(1 m³/1,000 L) = n(8.314 m³Pa/molK)(65+273 K)
Calculating for n,
n = 0.0445 mole of water

Considering the molar mass of water is 18 g/mol,
The mass of the vaporized water = 0.0445 * 18 = 0.8 g of water evaporated

Therefore,
The fraction of water that vaporized = 0.8/1.2 * 100 = 66.7%

3 0

22 days ago