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
aliina [53]
3 years ago
5

which atom has a change in oxidation number of -3 in the following redox reaction K2Cr2O7 + H2O +S --> KOH + Cr2O3 +SO2

Chemistry
1 answer:
yaroslaw [1]3 years ago
6 0
You have to calculate the oxidation estates of the atoms in each compound.

I will start with K2Cr2O7 because I believe that Cr is the best candidate to reduce its oxidation number in 3 units.

In K2Cr2O7:

- K has oxidation state of 1+, then K2 has a charge of 2* (1+) = 2+.

- O has oxidation state of 2*, then O7 has a charge of 7* (2-) = 14-.

That makes that Cr2 has charge of 14 - 2 = +12, so each Cr has +12/2 = +6 oxidation state.

In Cr2O3:

- O has oxidation state of 2-, then O3 has charge 3 * (2-) = - 6

- Then, Cr2 has charge 6+, and each Cr has charge 6+ / 2 = 3+.

So, we have seen that Cr reduced its oxidation state in 3 units, from 6+ to 3+.

Answer: Cr has a change in oxidation number of - 3.
You might be interested in
Which of the following summertime activities consists solely of physical change?
Evgen [1.6K]
A: making s sandcastle. This is because water and sand is only a mixture, so they do not react with each other. All the rest include chemical reactions!
5 0
3 years ago
How do atmospheric updrafts affect clouds?
Andru [333]

Answer:

Updrafts characterize a storm's early development, during which warm air rises to the level where condensation begins and precipitation starts to develop. In a mature storm, updrafts are present alongside downdrafts caused by cooling and by falling precipitation.

Hope it helps  

Have a great Day : P

6 0
3 years ago
How many photons are produced in a laser pulse of 0.862 J at 691 nm?
Inga [223]
To calculate how many photons are in a certain amount of energy (joules) we need to know how much energy is in one photon.
Start by using two equations:
Energy of a photon = Frequency * Planck's constant (6.626 * 10^(-34) J-s)
Speed of light (constant 3 * 10^8 m/s) = Frequency * Wavelength
Which means:
frequency = Speed of Light / Wavelength
So energy of a photon = (Speed of light * Planck's constant)/(Wavelength)
You may have seen this equation as E = hc/<span>λ</span>
We have a wavelength of 691 nm or 691 * 10^-9 meters
So we can plug in all of our knowns:
E = (6.626 * 10^(-34) J-s) * (3.00 * 10^8 m/s) / (691 * 10^-9 m) = 
2.88 * 10^(-19) joules per photon
Now we have joules per photon, and the total number of joules (0.862 joules)
,so divide joules by joules per photon, and we have the number of photons:
0.862 J/ (2.88 * 10^(-19) J/photon) = 3.00 * 10^18 photons.

4 0
3 years ago
Which of the following is a producer?
stellarik [79]
C a giraffe that eats the leaves off trees
7 0
3 years ago
Read 2 more answers
An alkanol contains 37.5 carbon
kow [346]

Answer:

Empirical formula is CH₄

Molecular formula = C₂H₈

Explanation:

Mass of carbon = 37.5 g

Mass of hydrogen = 12.5 g

Molecular weight = 32 g/mol

Molecular formula = ?

Empirical formula = ?

Solution:

Number of gram atoms of C = 37.5 g /12g/mol = 3.125

Number of gram atoms of H = 12.5 g / 1.008 g/mol= 12.4

Atomic ratio:

C                 :            H            

3.125/3.125   :       12.4 /3.125

    1                :            4          

C : H : = 1 : 4

Empirical formula is CH₄

Molecular formula:

Molecular formula = n (empirical formula)

n = molar mass of compound / empirical formula mass

n = 32  / 16

n = 2

Molecular formula = n (empirical formula)

Molecular formula = 2 ( CH₄)

Molecular formula = C₂H₈

3 0
3 years ago
Other questions:
  • Tear gas has the composition 40.25% carbon, 6.19% hydrogen, 8.94% oxygen, 44.62% bromine. what is the empirical formula of this
    14·2 answers
  • A hiker seals a plastic bag that contains dried fruits before he climbs a mountain. What will most likely happen to the plastic
    10·2 answers
  • Calcium hydride reacts with water to form calcium hydroxide and hydrogen gas. The balanced equation for this is CaH2 + 2H2O ---&
    7·2 answers
  • Given the following balanced equation determine the amount of MgCl2 that can be produced from 65.0 grams of Mg. Mg + HCl --&gt;
    12·1 answer
  • Which of the following is not produced in
    10·2 answers
  • Antacids, such as Alka-Seltzer, use the reaction of sodium bicarbonate with citric acid in water solution to produce a fizz as f
    13·1 answer
  • 5.75 moles of H2 gas to liters at STP
    5·1 answer
  • Force LaTeX: F=maF = m a
    6·2 answers
  • In the pictured reaction, NH4, would be acting as the
    10·1 answer
  • Th ph value of milk is close to
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!