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
horsena [70]
3 years ago
13

Someone please do this!!!

Chemistry
1 answer:
Lilit [14]3 years ago
4 0

Answer:

1) Fe = 69.9%

O = 31.1%

2) H = 5.19%

O = 16.5%

N = 28.9%

C = 49.5%

Explanation:

One easy way to do percent compositions is to assume you have 100g of a substance.

1) Lets say we have 100g of Fe2O3.

The total molar mass would be:

= 55.845*2+15.999*3 = 159.687

The molar mass of the Fe2 alone is:

=55.845*2 = 111.69

Thus, the grams of Fe2(out of a 100) could be calculated by multiplying 100g * the molar mass ratio of Fe2 to the whole:

= 100g *\frac{111.69}{159.687} = 69.9431

Which is approximately 69.9%.

We can find the amount of O3 by simply subtracting, as the rest of the compound is made of O3. Thus, the % composition of O3 is 31.1%

You can then do this same process to the next question, getting us the following:

H = 5.19%

O = 16.5%

N = 28.9%

C = 49.5%

You might be interested in
A boy with pneumonia has lungs with a volume of 1.7 L that fill with 0.070 mol of air when he inhales. When he exhales, his lung
BlackZzzverrR [31]

Answer:

0.053moles

Explanation:

Hello,

To calculate the number of moles of gas remaining in his after he exhale, we'll have to use Avogadro's law which states that the volume of a given mass of gas is directly proportional to its number of moles provided that temperature and pressure are kept constant. Mathematically,

V = kN, k = V / N

V1 / N1 = V2 / N2= V3 / N3 = Vx / Nx

V1 = 1.7L

N1 = 0.070mol

V2 = 1.3L

N2 = ?

From the above equation,

V1 / N1 = V2 / N2

Make N2 the subject of formula

N2 = (N1 × V2) / V1

N2 = (0.07 × 1.3) / 1.7

N2 = 0.053mol

The number of moles of gas in his lungs when he exhale is 0.053 moles

7 0
3 years ago
What changes in space result from the death of massive stars?
lana [24]

Whenever the fuel is being used up, a star explodes and the energy leakage from a star's core ceases.

Explanation:

The dying star expands in the "Red Giant," before even the inevitable collapse starts, due to nuclear reactions just outside of the core.

It becomes a white dwarf star when the star has almost the same density as the Sun. If it's much larger, a supernova explosion could take place and leave a neutron star away. However, if it is very large–at least three times the Sun's mass–the crumbling core of the star, nothing will ever stop it from crumbling. The star is imploding into a black hole, an endless gravitational loop in space.

6 0
3 years ago
What is the primary role of the United States Bureau of Counterterrorism?
zubka84 [21]

o advance counterterrorism efforts in other countries

7 0
3 years ago
Read 2 more answers
Choose the correct statement.
Studentka2010 [4]

Answer:

B) Cations lose electrons having a charge of positive.

Explanation:

Hello there!

In this case, it is widely known that ions are classified as positive cations and negative anions, since the former is produced when a metal loses electrons and the latter when a nonmetal gains electrons; in such a way, the correct choice is:

B) Cations lose electrons having a charge of positive.

Best regards!

6 0
3 years ago
If a chemical reaction occurs in a direction that has a positive change in entropy thenGroup of answer choicesthe change in enth
mezya [45]

Answer:

The reaction must be spontaneous, the disorder of the system increases.

Explanation:

By the Second Law of Thermodynamics, a positive change in entropy is due to a net input heat, and entropy is a measure of the grade of disorder within the system. The net input heat means that resultant goes to the system from the surroundings.

By the First Law of Thermodynamics, a net input heat is due to a positive change in enthalpy.

The reaction is endothermic and spontaneous (since change in entropy is positive).

6 0
3 years ago
Other questions:
  • If 192 g of O are produced, how many grams of hydrogen must react with it
    6·1 answer
  • Generally how does the first ionization energy vary as the atomic number increases going across a period
    10·1 answer
  • A particular coal contains 2.5% sulfur by mass. When this coal is burned, the sulfur is converted into sulfur dioxide gas. The s
    9·1 answer
  • As the tempreture of a liquid increases the solubility of a liquid of that liquid
    9·1 answer
  • In a test of an automobile engine 1.00 L of octane (702 g) is burned, but only 1.84 kg of carbon dioxide is produced. What is th
    12·1 answer
  • Stable electron configurations are likely to contain ____.
    14·2 answers
  • 1 Mr. Chavez paid $14.32 total for 8 protein bars.
    14·1 answer
  • How many moles are in 5.34 x 10*21 particles of Nitrogen?
    15·1 answer
  • 2 SO3 (g) + Heat <-----> 2 SO2 (g) + O2 (g)
    13·1 answer
  • Is Elisa getting the right amount of sleep??
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!