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
dezoksy [38]
3 years ago
15

Which one is a chemical reaction? Why?

Chemistry
1 answer:
Alex17521 [72]3 years ago
3 0

Answer:

Copper turns green on exposure to air

Explanation:

Liquid water freezes to form ice: Physical change

Reason: Water can melt back when it becomes ice.

Copper turns green on exposure to air: Chemical change

Reason: The copper can not change back from the green state when it turns green.

You might be interested in
A certain protein was found to contain 0.292% manganese by mass. Determine the minimum molecular mass of the protein.
Lisa [10]
55u \ \ \ \ \ \ \Rightarrow \ \ \ \ \ 0,292\%\\
x \ \ \ \ \ \ \ \ \ \Rightarrow \ \ \ \ \ 100\%\\\\
x = \frac{55u*100\%}{0,292\%}\approx18835,62u
4 0
3 years ago
What is the correct electron configuration for an element with 5 electrons in
Harlamova29_29 [7]

Answer:

it is c

Explanation:

5 0
3 years ago
What is the ratio of [a–]/[ha] at ph 3.75? the pka of formic acid (methanoic acid, h–cooh) is 3.75?
Vikentia [17]

The formula for pH given the pKa and the concentrations are:

pH = pKa + log [a–]/[ha]

<span>
Therefore calculating:</span>

3.75 = 3.75 + log [a–]/[ha]

log [a–]/[ha] = 0

[a–]/[ha] = 10^0

<span>[a–]/[ha] = 1</span>

3 0
3 years ago
Read 2 more answers
Which process releases the energy that eventually produces lighting in a thunderstorm
Elena L [17]
The process that releases energy which causes lightning is known as Glaciation
5 0
3 years ago
Summarize the five points of Dalton’s atomic theory, and explain at least one change that occurred to the atomic theory because
Umnica [9.8K]
The postulates of Dalton's theory were:
1) Elements are made of extremely small particles called atoms
2) <span>Atoms of a given element are identical in size, mass, and other properties
</span>3) <span>Atoms cannot be subdivided, created, or destroyed</span>
4) Atoms combine in whole number ratio to form compounds
5) Chemical reactions are the rearrangement of atoms
The third postulate has been disproved by modern science, in which the atom has been split and been subdivided into smaller parts such as the neutron, proton and electron, which are further subdivided into quarks, gluons, and kaons.
The second postulate was also disproved upon the discovery of isotopes.
4 0
3 years ago
Read 2 more answers
Other questions:
  • If an element has an atomic number of 20 and a mass number of 41, what is the :
    11·1 answer
  • Which SI units can be used to describe an object’s volume?
    15·1 answer
  • What is an isotope?
    6·1 answer
  • A compound ‘X’ is used for drinking, has pH =7.Its acidified solution undergoes decomposition in presence of electricity to prod
    9·1 answer
  • What, if anything is wrong with the model of the solar system shown below ? Give me a big or small answer
    6·1 answer
  • The high concentration of carbon dioxide (CO2) in the atmosphere of Mars inhibits infrared radiation from escaping and keeps the
    11·1 answer
  • List the 5 signs of a CHEMICAL REACTION
    6·1 answer
  • How many moles are in 75 grams of potassium
    9·2 answers
  • An expression is show below. - 1 2/3 - x
    12·1 answer
  • What patterns in the rock layer fossils helped you identify an extinction?
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!