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
astraxan [27]
3 years ago
13

When does a change in energy occur?

Chemistry
1 answer:
MrRa [10]3 years ago
6 0
3. in every chemical or physical change
You might be interested in
How many elements are in the second group? (column)
zavuch27 [327]
Of the periodic table?
6 0
4 years ago
A student carried out a titration using HC2H3O2(aq) and NaOH(aq). The net ionic equation for the neutralization reaction that oc
cluponka [151]

Answer:

The  ratio of HC2H3O2(aq) in the flask after the addition of 5.0mL of NaOH(aq) to HC2H3O2(aq) in the flask after the addition of 1.0mL of NaOH(aq) is 15 : 19 .

Explanation:

HC2H3O2 is  CH₃⁻ COOH, which is also known as Acetic acid.

IUPAC name of this compound is Ethanoic acid.

Acetic acid has a basicity of 1. so there is one acidic hydrogen is acetic acid.

Given that, equivalence point was reached when 20.0mL of NaOH is added.

let the normality of acetic acid is N₁ and that of NaOH is N₂.

    volume of acetic acid is V₁ and that of NaOH is V₂.  

 Equivalence point occurs when, N₁ × V₁ =  N₂ × V₂.

⇒  N₁ × V₁ =  N₂ × 20.

after the addition of 5.0mL of NaOH(aq), remaining N₁ × V°  = N₂ × (20 - 5).

                                                                                                  = N₂ × 15.

after the addition of 1.0mL of NaOH(aq), remaining N₁ × Vˣ = N₂ × (20 - 1).

                                                                                                  = N₂ × 19.

⇒ V° : Vˣ = 15 : 19 .

⇒

7 0
3 years ago
Describe how scientists use models to make predictions.
Rashid [163]

Models help scientists to make predictions about complex systems. Some models are something that you can see or touch. ... Climate models can predict how climate will change as certain gases are added to the atmosphere. To test how good a model is, scientists might start a test run at a time in the past.

6 0
3 years ago
Read 2 more answers
I have four questions.
navik [9.2K]
Abca I think it’s right not sure
3 0
3 years ago
Read 2 more answers
A balloon contains 0.950 mol of nitrogen gas and has a volume of 25.5 L. How many grams of N2 should be released from the balloo
kirill [66]
Answer:
Mass released = 8.6 g
Explanation:
Given data:
Initial number of moles nitrogen= 0.950 mol
Initial volume = 25.5 L
Final mass of nitrogen released = ?
Final volume = 17.3 L
Solution:
Formula:
V₁/n₁ = V₂/n₂
25.5 L / 0.950 mol = 17.3 L/n₂
n₂ = 17.3 L× 0.950 mol/25.5 L
n₂ = 16.435 L.mol /25.5 L
n₂ = 0.644 mol
Initial mass of nitrogen:
Mass = number of moles × molar mass
Mass = 0.950 mol × 28 g/mol
Mass = 26.6 g
Final mass of nitrogen:
Mass = number of moles × molar mass
Mass = 0.644 mol × 28 g/mol
Mass = 18.0 g
Mass released = initial mass - final mass
Mass released = 26.6 g - 18.0 g
Mass released = 8.6 g
3 0
3 years ago
Other questions:
  • Complete the word equation for making a salt. _________ + __________ → salt
    7·2 answers
  • Determine the volume of sodium hydroxide added to the flask from the beret.
    7·1 answer
  • Goot is conducting an experiment to see whether goldfish eat more flakes or pellets. He thinks that the fish will choose the fla
    8·2 answers
  • PLZ HELP ME WITH MY WORK​
    14·1 answer
  • Why is it commonly believed that carbon dioxide is responsible for global warming?<br>​
    15·1 answer
  • A gas is contained in a horizontal cylinder with a moveable piston of cross-sectional area 0.33\text{ m}^20.33 m 2 . The region
    12·1 answer
  • Carboxyl groups contain only nonpolar bonds.​
    8·1 answer
  • Pls help asap!!! BrainIdentify one source of carbon that can be found in each of these four spheres: atmosphere (air), geosphere
    14·2 answers
  • If the pH of a solution is 7, what is the pOH?
    13·1 answer
  • Need to balance these equations
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!