1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Nataly_w [17]
3 years ago
13

A solution of potassium cyanide, KCN, is made by dissolving 3.2 g of KCN in water. When this solution reacts with excess hydroch

loric acid, HCl, it produces 0.30 g of poisonous hydrogen cyanide gas, HCN.
KCN + HCl --> KCl + HCN

(a) Calculate the theoretical yield of HCN.

(b) Calculate the percent yield of HCN.
Chemistry
2 answers:
lesantik [10]3 years ago
6 0

Answer:

The theoretical yield HCN is 1.33 grams

The percent yield HCN is 22.56 %

Explanation:

Step 1: Data given

Mass of KCN = 3.2 grams

Molar mass KCN = 65.12 g/mol

Mass of HCN produced = 0.30 grams

Step 2: The balanced equation

KCN + HCl --> KCl + HCN

Step 3: Calculate moles KCN

Moles KCN = mass KCN / moalr mass KCN

Moles KCN = 3.2 grams / 65.12 g/mol

Moles KCN = 0.0491 moles

Step 4: Calculate moles HCN

For 1 mol KCN we need 1 mol HCl to produce 1 mol KCl and 1 mol HCN

For 0.0491 moles HCN we'll have 0.0491 moles HCN

Step 5: Calculate mass HCN

Mass HCN = moles HCN * molar mass HCN

Mass HCN = 0.0491 moles * 27.03 g/mol

Mass HCN = 1.33 grams = the theoretical yield

Step 6: Calculate the percent yield HCN

Percent yield = (actual yiel / theoretical yield) * 100 %

Percent yield = (0.30 grams / 1.33 grams)

Percent yield = 22.56 %

Rama09 [41]3 years ago
3 0

Answer:

22.7%

Explanation:

We must first put down the equation of reaction to guide our work while solving the problem.

KCN(aq) + HCl (aq)--> KCl(aq) + HCN(aq)

The questions specifically state that HCl is in excess so KCN is the limiting reactant.

Number of moles of KCN reacted= mass of KCN reacted / molar mass of KCN

Mass of KCN reacted= 3.2 g

Molar mass of KCN= 65.12 g/mol

Number of moles of KCN= 3.2/65.12 g/mol= 0.049 moles

Theoretical yield of HCN is obtained thus;

From the reaction equation;

1 mol of KCN produced 1 mole of HCN thus 0.049 moles of KCN will produce 0.049 moles of HCN.

Mass of HCN = number of moles ×molar mass

Molar mass of HCN= 27.0253 g/mol

Hence mass of HCN produced= 0.049mol × 27.0253 g/mol= 1.32g of HCN

Actual yield of HCN= 0.30g

% yield= actual yield/ theoretical yield ×100

% yield= 0.30/1.32 ×100

%yield= 22.7%

You might be interested in
A student made the following diagram to represent cellular respiration.
Ratling [72]
The correct answer is A, Water is not used up during this process. This is because when cellular respiration occurs oxygen and glucose combine. When this takes place water is left behind when carbon is separated from glucose. Because water is being left behind it is not being used up in this process. 
3 0
3 years ago
Read 2 more answers
Ameaba is which protozoan​
Vikki [24]

Answer: genus

Explanation:

Amoebas do not form a single taxonomic group; instead, they are found in every major lineage of eukaryotic organisms. Amoeboid cells occur not only among the protozoa, but also in fungi, algae, and animals.

4 0
3 years ago
Read 2 more answers
view each ecosystem at your table. Think about the resources that are necessary in order for each to be successful. List all of
TiliK225 [7]

Answer:

Organisms compete for the resources they need to which are survive- air, water, food, and space.

7 0
3 years ago
Read 2 more answers
How would you prepare a 1.00L solution of 2.00 M sodium hydroxide<br> (NaOH)*
Ede4ka [16]

Answer:

Explanation:

Molar mass of sodium hydroxide is = 100

any compund with its molar mass dissovled in 1L itres solution gives rise to 1M solution

40 g ------> 1L ---->1M

Xg  ------>1L------>2M

X g= 40*1*2/1*1 =80 gram

3 0
3 years ago
Sodium fluoroacetate (NaO₂C₂H₂F) is a common poison used in New Zealand to control invasive species, such as rats. It can be pre
NISA [10]

Answer:

-219

Explanation:

1.5(339) - 1.5(485) = -219

7 0
3 years ago
Other questions:
  • Consider a solution that contains 60.0% r isomer and 40.0% s isomer. if the observed specific rotation of the mixture is –43.0°,
    5·1 answer
  • In order to digest food, the human body requires ​
    12·1 answer
  • A solution contains naphthalene (c10h8) dissolved in hexane (c6h14) at a concentration of 10.00 % naphthalene by mass. part a ca
    10·2 answers
  • Which of these processes occur when water changes to ice?
    12·2 answers
  • You might need:
    6·1 answer
  • Чому вирівнювання хімічних рівнянь є обов´язковим
    6·1 answer
  • How is the size of silver nanoparticles different from normal sized silver?
    9·1 answer
  • Ethanol absorbs more energy than water because it has a lower heat capacity <br><br> True or false?
    10·1 answer
  • we have not visited jupiter to collect samples, so how do we know what the atmosphere is composed of?
    14·1 answer
  • What type of chemical reaction is the reaction below?Fe2O3 + 3 Mg --&gt; 2 Fe + 3 MgO
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!