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
ludmilkaskok [199]
3 years ago
15

A. Calculate the empirical formula of a molecule with percent compositions: 55.3% potassium (K), 14.6% phosphorus (P), and 30.1%

oxygen (O). Complete the table below to help with the calculations. (5 points)
Element
Mass Percent
Mass of 100g of the compound
Number of Moles in 100 G

K
55.3%


P
14.6%


O
30.1%

Chemistry
2 answers:
dezoksy [38]3 years ago
8 0

Answer:

empirical formula => K₃PO₄

Explanation:

For empirical formula problems, if not given in percent per 100 weight convert given data to percent per 100 weight and then follow the following sequence:

% => grams/100wt => moles => mole ratio => reduce mole ratio to smallest whole no. ratio => empirical ratio

K => 55.3% => 55.3 grams/100 wt => 55.3 g/ 39.0 g·mol⁻¹ = 1.418 mol

P => 14.6% => 14.6 grams/100 wt => 14.6 g/ 30.9 g·mol⁻¹ = 0.4725 mol

O => 30.1% => 30.1 grams/100 wt => 30.1 g/16.0 g·mol⁻¹ = 1.8813 mol

K : P : O => 1.418 : 0.4725 : 1.8813

Mole ratio => K : P : O => 1.418 : 0.4725 : 1.8813  

Reduce mole ratio by dividing all values by smallest mole value ...  

K : P : O => 1.418/0.4725 : 0.4725/0.4725 : 1.8813/0.4725 => 3 : 1 : 4  

Multiply reduced ratio by whole number multiple that will give a set of whole number values => empirical ratio. For this problem, whole no. multiple = 1 => empirical ratio => 3 : 1 : 4

empirical formula => K₃PO₄

______________________________

moles per 100wt.

formula weight = 3K + 1P + 4O = [3(39) + 1(30.9) + 4(16)] g/mol = 211.9 g/mol

moles per 100wt = 100 g / 211.9 g·mol⁻¹ = 0.472 mol. K₃PO₄

Otrada [13]3 years ago
6 0
The way you calculate the empirical formula is to firstly assume 100g. To find each elements moles you take each elements percentage listed, times it by one mole and divide it by its atomic mass. (ex: moles of K =55.3g x 1 mole/39.1g, therefore there is 1.41432225 moles of Potassium) Once you’ve completed this for every element you list each elements symbol beside it’s number of moles and divide by the smallest number because it can only go into its self once. After you’ve done this, you’ve found your empirical formula, which is the simplest whole number ratio of atoms in a compound. I’ve added an example of a empirical question I completed last semester :)

You might be interested in
For ethanol, propanol, and n-butanol the boiling points, surface tensions, and viscosities all increase. what is the reason for
Contact [7]
Moving from Ethanol through Propanol to Butanol the physical properties like boiling points, surface tension and viscosity increases because of the increases in intermolecular interactions between the molecules of given compounds.

Explanation:
                   Ethanol, propanol and butanol all have hydroxyl groups in common, means all have hydrogen bond intractions between their molecules. So, taking the hydrogen bonding interaction constant we are left with only the difference in the number of carbon atoms.
                    Butanol has the greatest physical properties than other two because it has four carbon atom chain. So, as we know the London Dispersion forces or Van der Waal forces increases with increase in molecular size and chain length of hydrocarbon.
                    Therefore, the strength of London forces is greater in butanol than other two while ethanol has the smallest chain comparatively hence, lowest physical properties.  
3 0
2 years ago
HELPPP
kolbaska11 [484]
B is the answer I think hope this helps
6 0
3 years ago
What other signs provide evidence of chemical reactions and show that a chemical change has occurred?
Dmitry_Shevchenko [17]
Color change
new substance formed
heat or light change
new smell
irreversible 
4 0
3 years ago
1. The side-by-side overlap of p orbitals produces what kind of bond?
Dmitry_Shevchenko [17]
A pi bond... hope this helps!!!!!
4 0
2 years ago
Read 2 more answers
What expression approximates the volume of O2 consumed, measure at STP, when 55 g of Al reacts completely with excess O2?2 Al(s)
nikdorinn [45]

Answer : The volume of O_2 consumed are, 0.75\times 2\times 22.4 L.

Explanation :

The balanced chemical reaction will be:

4Al(s)+3O_2(g)\rightarrow 2Al_2O_3(s)

First we have to calculate the moles of Al.

\text{Moles of }Al=\frac{\text{Mass of }Al}{\text{Molar mass of }Al}

Molar mass of Al = 27 g/mole

\text{Moles of }Al=\frac{55g}{27g/mol}=2mole

Now we have to calculate the moles of O_2.

From the reaction we conclude that,

As, 4 mole of Al react with 3 moles of O_2

So, 2 mole of Al react with \frac{3}{4}\times 2=0.75\times 2 moles of O_2

Now we have to calculate the volume of O_2 consumed.

As we know that, 1 mole of substance occupies 22.4 liter volume of gas.

As, 1 mole of O_2 occupies 22.4 liter volume of O_2 gas

So, 0.75\times 2 mole of O_2 occupies 0.75\times 2\times 22.4 liter volume of O_2 gas

Therefore, the volume of O_2 consumed are, 0.75\times 2\times 22.4 L.

3 0
3 years ago
Other questions:
  • Explain why a single atom of hydrogen cannot produce all four hydrogen spectral lines simultaneously.
    7·1 answer
  • Is a substance that a filter can seperate into two parts a mixture or a pure substance?
    14·1 answer
  • What are 5 examples of gases found at home?
    10·2 answers
  • Hurry plz<br> How does distance affect the strength of an electric force?
    6·2 answers
  • Acid indigestion is sometimes neutralized with an antacid such as magnesium hydroxide (Mg(OH)2). What products will be released
    12·1 answer
  • At what temp does h2o melt
    12·2 answers
  • Select whether the statement is for Speed, Velocity, or Acceleration.
    9·1 answer
  • Plz help, asap, no links and don't put answer if you don't know. Explain also!
    15·1 answer
  • In an acid/base titration where NaOH(aq) is the titrant and HCl(aq) is the analyte, what is true about the moles of each reactan
    7·1 answer
  • A radioactive substance has a half-life of 5 million years. What is the age of a rock in which 25% of the original radioactive a
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!