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
Dafna11 [192]
3 years ago
9

7. How many significant figures are in the following numbers?

Chemistry
1 answer:
Vlad1618 [11]3 years ago
7 0
There are
A. 6 significant figures
B.5 sig figs
C.2 sig figs
D.5 sig figs
You might be interested in
Consider the process used to produce iron metal from its ore.
Dmitry_Shevchenko [17]

Answer:

223.4 grams of iron can be produced from 2.5 moles of Fe2O3 and 6.0 moles of CO.

Explanation:

The balanced reaction is:

Fe₂O₃ (s) + 3 CO(g) → 2 Fe(s) + 3 CO₂ (g)

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of reactant and product participate in the reaction:

  • Fe₂O₃: 1 mole
  • CO: 3 moles
  • Fe: 2 moles
  • CO₂: 3 moles

Being:

  • Fe: 55.85 g/mole
  • O: 16 g/mole
  • C: 12 g/mole

the molar mass of the compounds participating in the reaction is:

  • Fe₂O₃: 2*55.85 g/mole + 3*16 g/mole= 159.7 g/mole
  • CO: 12 g/mole + 16 g/mole= 28 g/mole
  • Fe: 55.85 g/mole
  • CO₂: 12 g/mole + 2*16 g/mole= 44 g/mole

Then, by stoichiometry of the reaction, the following quantities participate in the reaction:

  • Fe₂O₃: 1 mole* 159.7 g/mole= 159.7 g
  • CO: 3 moles* 28 g/mole= 84 g
  • Fe: 2 moles* 55.85 g/mole= 111.7 g
  • CO₂: 3 moles* 44 g/mole= 132 g

The limiting reagent is one that is consumed first in its entirety, determining the amount of product in the reaction. When the limiting reagent is finished, the chemical reaction will stop.

So, first of all, you can apply the following rule of three: if by reaction stoichiometry 1 mole of Fe₂O₃ reacts with 3 moles of CO, then 2.5 moles of Fe₂O₃ react with how many moles of CO?

moles of CO=\frac{2.5 moles of Fe_{2} O_{3}*3 moles of CO }{1 mole of Fe_{2} O_{3}}

moles of CO= 7.5

But 7.5 moles of CO are not available, 6.0 moles are available. Since you have less moles than you need to react with 2.5 moles of Fe₂O₃, CO will be the limiting reagent.

Now you can apply the following rule of three: if by reaction stoichiometry 3 moles of CO produce with 111.7 grams of Fe, then 6 moles of CO will produce how much mass of Fe?

mass of Fe=\frac{6 moles of CO*111.7 grams of Fe}{3 moles of CO}

mass of Fe= 223.4 grams

<u><em>223.4 grams of iron can be produced from 2.5 moles of Fe2O3 and 6.0 moles of CO.</em></u>

5 0
3 years ago
calculate the volume of carbon dioxide of room temperature and pressure obtained from 30 grams of glucose​
ivanzaharov [21]

Answer:

A

Explanation:

4 0
3 years ago
Why is the Atlantic Ocean growing larger, but the Pacific Ocean is growing smaller?
Anastasy [175]

Answer:

A.The Atlantic Ocean has more mid-ocean ridges than the Pacific Ocean so that keeps it growing larger.

Explanation:

Atlantic ocean is getting bigger because of the presence of spreading centers (divergent plate boundary). ... Pacific Ocean is getting smaller because the pacific plate is subducting along the subduction zones. Subduction zones are areas where old, dense plate subducts beneath a less dense plate.

7 0
3 years ago
Tgc-rqbk-gnr Hlo friends lets join to​
kaheart [24]

Ok Hello I"m joining to.

4 0
3 years ago
Question 3 of 10
olga55 [171]

Answer:

A. A disease stops an organ from doing its job and causes

imbalance in the body.

Explanation:

Disease and cellular malfunction can be caused in two basic ways: by deficiency or toxicity

7 0
3 years ago
Other questions:
  • PLEASE HURRY!! ONLY ANSWER IF YOU KNOW FOR SURE
    8·1 answer
  • How many equivalent resonance forms can be drawn for co32-? (carbon is the central atom.) how many equivalent resonance forms ca
    8·1 answer
  • How do you know how many electrons an element will gain or lose in forming an ion?
    7·1 answer
  • What is the empirical formula for a compound that contains 12.62% li, 29.17% s, and 58.21% o?
    6·1 answer
  • Calculate the expansion work done against a constant external pressure of 0.995 atm and at a constant temperature of 19°C. Assum
    11·1 answer
  • A certain element exists as two different isotopes. 76.00% of its atoms have a mass of 35.00 amu and 24.00% of its atoms have a
    11·1 answer
  • What is the activation energy of a reaction whose rate constant doubles when the temperature is increased from 300K to 350K (ass
    7·1 answer
  • The Periodic Table of elements is arranged by: atomic number atomic mass number of electrons number of neutrons
    10·2 answers
  • Why would an atom have zero charge
    10·1 answer
  • Calculate the percent by mass of 4.35g of Na I dissolved in 105g of water​
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!