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
Misha Larkins [42]
3 years ago
11

An unknown substance has the composition of 77.87% c, 11.76% h and 10.37% o. the compound has a molar mass of 154.25 g/mole. wha

t is the molecular formula?
Chemistry
1 answer:
frutty [35]3 years ago
6 0
We need to first calculate the empirical formula. Empirical formula is the simplest ratio of whole numbers of components in a compound,
Mass percentages have been given. We need to then calculate for 100 g of the compound 
                               C                     H                           O
mass                    77.87 g              11.76 g                 <span>10.37 g
number of moles  77.87/12            11.76/1                 10.37/16
moles                  = 6.48                  = 11.76                 =0.648
divide by least number of moles 
                              6.48/0.648       11.76/0.648            0.648/0.648
                              = 10                 =18.1                      = 1
rounded off
C - 10 , H - 18 and O - 1
empirical formula - C</span>₁₀H₁₈O
mass of empirical unit = 12 x 10 + 1x 18 + 16 = 120 + 18 + 16 = 154 
number of empirical units = molecular mass / mass of one empirical unit 
                                         = 154.25 / 154 = 1.00 
Therefore molecular formula = C₁₀H₁₈O
You might be interested in
What is the purpose of the scientific method?
Umnica [9.8K]

Answer:

The Scientific Method helps you put together experiments, use data to find conclusions and interpret them.

Explanation:

pls brainliest thank you

7 0
2 years ago
You are given mixture made of 290 grams of water and 14.2 grams of salt. Determine the % by mass of salt in the salt solution.
marishachu [46]

Answer:

Solution is 4.67% by mass of salt

Explanation:

% by mass is the concentration that defines the mass of solute in 100g of solution.

In this case we have to find out the mass of solution with the data given:

Mass of solution = Mass of solute + Mass of solvent

Solute:  Salt → 14.2 g

Solvent: Water → 290 g

Solution's mass = 14.2 g + 290g = 304.2 g

% by mass = (mass of solute / mass of solution) . 100

(14.2 g / 304.2g) . 100 = 4.67 %

3 0
3 years ago
Most acid precipitation results from the combination of _____ with water in the atmosphere, forming strong acids that fall with
aleksley [76]

Answer:

             Most acid precipitation results from the combination of <u>Sulfur Oxides and Nitrogen Oxides</u> with water in the atmosphere, forming strong acids that fall with rain or snow.

Explanation:

                    Acid rain is said to be that rain which contains high concentration of H⁺ ions. The main source of acid rain is the elimination of NOₓ (Nitrogen Oxides) and SOₓ (Sulfur Oxides) from different means in industries and other combustion processes on earth.

Examples:

                                 SO₂  +  H₂O     →     H₂SO₄

                                 NO₂  +  OH°    →     HNO₃

From above examples it can be seen that the sulfur and nitrogen oxides when reacted with water forms strong acids. These acids come along with rain water and causes different problems to living organisms and non living objects like buildings.

4 0
2 years ago
A mixture of hydrogen and argon gases is maintained in a 6.47 L flask at a pressure of 3.43 atm and a temperature of 85 °C. If t
11Alexandr11 [23.1K]

Answer:

The mixture contains 8.23 g of Ar

Explanation:

Let's solve this with the Ideal Gases Law

Total pressure of a mixture = (Total moles . R . T) / V

We convert T° from °C to K → 85°C + 273 = 358K

3.43 atm = (Moles . 0.082 L.atm/mol.K . 358K) / 6.47L

(3.43 atm . 6.47L) / (0.082 L.atm/mol.K . 358K) = Moles

0.756= Total moles from the mixture

Moles of Ar + Moles of H₂ = 0.756 moles

Moles of Ar + 1.10 g / 2g/mol = 0.756 moles

Moles of Ar = 0.756 moles - 0.55 moles H₂ → 0.206

We convert the moles to g → 0.206 mol . 39.95 g / 1 mol = 8.23 g

8 0
2 years ago
Read 2 more answers
Use bond energies to calculate δhrxn for the reaction. n2(g)+3cl2(g)→2ncl3(g)
Jobisdone [24]
ΔHrxn = ΣδΗ(bond breaking) - ΣδΗ(bond making)

Bond enthalpies,
N ≡ N ⇒ 945 kJ mol⁻¹
N - Cl ⇒ 192 kJ mol⁻¹
Cl - Cl⇒ 242 kJ mol⁻¹

According to the balanced equation,
ΣδΗ(bond breaking)  = N ≡ N x 1 + Cl - Cl x 3
                                  = 945 + 3(242)
                                  = 1671 kJ mol⁻¹
ΣδΗ(bond making)    = N - Cl x 3 x 2
                                 = 192 x 6
                                 = 1152 kJ mol⁻¹

δHrxn = ΣδΗ(bond breaking) - ΣδΗ(bond making)
          = 1671 kJ mol⁻¹ - 1152 kJ mol⁻¹
          = 519 kJ mol⁻¹
3 0
3 years ago
Read 2 more answers
Other questions:
  • How many elements are there in the first column of the periodic table?
    10·1 answer
  • Which rays has the highest frequency?
    10·1 answer
  • The graph of y = 3x2 + 12x + 11 is shown.
    8·1 answer
  • What property do all types of waves share?
    14·1 answer
  • What is the criteria to place an element in a particular group?
    10·1 answer
  • Why does Magnesium and Copper can't react with Sodium hydroxide ?
    9·1 answer
  • Chemistry and physics are a branch of what science?
    13·1 answer
  • Determine the mass in grams of 0.600 mol of oxygen atoms ( 32 grams x1mole/(mass of element)
    13·1 answer
  • Choose one region on the world map. How does the climate there differ during El Niño and La Niña?
    6·2 answers
  • State the property of a conducting wire which is utilised in making electric fuse.
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!