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
Angelina_Jolie [31]
3 years ago
9

Calculate the number of ammonia molecules in 3.9 g.

Chemistry
1 answer:
disa [49]3 years ago
6 0
•3.9g of ammonia
•molar mass of ammonia = 17.03g/mol

1st you have to covert grams to moles by dividing the mass of ammonia with the molar mass:

(3.9 g)/ (17.03g/mol) = 0.22900763mols

Then convert the moles to molecules by multiplying it with Avogadro’s number:

Avogadro’s number: 6.022 x 10^23


0.22900763mols x (6.022 x 10^23 molecs/mol)
= 1.38 x 10^23 molecules
You might be interested in
Write your question here (Keep it simple and clear to get the best answer) calculate the atomic weight of a metal when 125ml of
lana [24]

Answer:

The answer to your question is 24.32 g

Explanation:

Data

Atomic weight = ?

HCl volume = 125 ml

Molarity = 0.2

mass of metal = 0.304 g

Balanced chemical equation

                       M + 2HCl   ⇒  MCl₂  +  H₂

Process

1.- Calculate the moles of HCl

Molarity = moles / volume (L)

- Solve for moles

  moles = Molarity  x volume

  moles = 0.2 x 0.125

             = 0.025

2.- Calculate the moles of the Metal

                1 mol of M ----------------- 2 moles of HCl

                x                ----------------- 0.025 moles of HCl

                x = (0.025 x 1) / 2

                x = 0.0125 moles of HCl

3.- Calculate the atomic weight of the metal

                atomic weight ---------------- 1 mol

               0.304 g             ---------------0.0125 moles

               Atomic weight = (1 x 0.304) / 0.0125

               Atomic weight = 24.32 g    

             

7 0
3 years ago
Read 2 more answers
Questions
Ulleksa [173]

Answers:

See below  

Step-by-step explanation:

1. Most food energy

(a) Pringles

Heat from Pringles + heat absorbed by water = 0

m₁ΔH  + m₂CΔT = 0

1.984ΔH + 100 × 4.184 × 18 = 0

1.984ΔH + 7530 = 0

ΔH = -7530/1.984 = -3800 J/g

(b) Cheetos

0.884ΔH + 418.4 × 13 = 0

ΔH = -5400/0.884 = -6200 J/g

Cheetos give you more food energy per gram.

(c) Snickers

Food energy = 215 Cal/28 g × 4184 J/1 Cal = 32 000 J/g

The food energy from Cheetos is much less than that from a Snickers bar

2. Experimental uncertainty

The experimental values are almost certainly too low.

Your burning food is heating up the air around it, so much of the heat of combustion is lost to the atmosphere.

3. Percent efficiency

Experimental food energy = 3800 J/g

Actual food energy = 150 Cal/28 g × 4184 J/1 Cal = 22 000 J/g

% Efficiency = Experimental value/Actual value × 100 %

                    = 3800/22 000 × 100 %

                    = 17 %

6 0
3 years ago
Explain the importance of fingerprint record in criminal investigation.​
miss Akunina [59]

Answer:

One of the most important uses for fingerprints is to help investigators link one crime scene to another involving the same person. Fingerprint identification also helps investigators to track a criminal's record, their previous arrests and convictions, to aid in sentencing, probation, parole and pardoning decisions.

Explanation:

3 0
3 years ago
Red paint mixed with blue paint becomes purple. What is the most likely cause of this color change?
melamori03 [73]

Answer:

I might be late but when red paint and blue paint mix to become purple. its a <u>physical change</u>, so its C

Explanation:

5 0
3 years ago
Ocean waves are just one example of waves that can be used to study the properties of waves. Other examples include the ringing
astraxan [27]

Answer:

Light, sound, and waves in the ocean are common examples of waves. Sound and water waves are mechanical waves; meaning, they require a medium to travel through. The medium may be a solid, a liquid, or a gas, and the speed of the wave depends on the material properties of the medium through which it is traveling.

Explanation:

hope this helps

8 0
3 years ago
Read 2 more answers
Other questions:
  • In the axoneme, sidearms
    11·1 answer
  • Calculate the heat created by the food if the mass if the water is 100 g, the specific heat of water is 4.18 J/g°C and the chang
    5·1 answer
  • Which of the following is smaller than the atomic radius of beryllium? a. the ionic radius of beryllium b. the atomic radius of
    9·1 answer
  • What is boiling point
    14·1 answer
  • What did the photoelectric experiment demonstrate?
    15·1 answer
  • Help ASAP please! I don’t understand this at all.
    14·1 answer
  • How to do this question plz answer me ​
    15·1 answer
  • 1. El peso aproximado de la piel es de .
    10·1 answer
  • Two rabbit species, X and Y, live in an Arctic environment that is also populated by wolves. Species x turns white in the winter
    7·1 answer
  • A chemist prepares a solution of copper(II) sulfate by measuring out 17.2 of copper(II) sulfate into a volumetric flask and fill
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!