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
Bezzdna [24]
3 years ago
9

Which events represents a chemical change ?

Chemistry
2 answers:
8_murik_8 [283]3 years ago
5 0
D milk turning sour 
the other options are physical changes
yawa3891 [41]3 years ago
3 0
Hihi!

The answer would be D. milk turning sour! What happens when milk goes sour is it<span> ferment lactose at room temperature and which turns it into lactic acid. More acid means more hydrogen ions, a lower pH and a </span>sour<span> taste. Lower pH change the structure of proteins like casein, which gives </span>milk<span> its whiteness, so it curdles into clumps called curds! It's pretty gross!</span>

I hope I helped!
-Jailbaitasmr
You might be interested in
A 0.75M solution of CH3OH is prepared in 0.500 kg of water. How many moles of CH3OH are needed?
4vir4ik [10]

Answer:

We need 0.375 mol of CH3OH to prepare the solution

Explanation:

For the problem they give us the following data:

Solution concentration 0,75 M

Mass of Solvent is 0,5Kg

knowing that the density of water is 1g / mL,  we find the volume of water:

                           d = \frac{g}{mL} \\\\ V= \frac{g}{d}  = \frac{500g}{1 \frac{g}{mL} } = 500mL = 0,5 L

Now, find moles of CH_{3} OH are needed using the molarity equation:

                           M = \frac{ moles }{ V (L)} \\\\\\molesCH_{3}OH  = M . V(L) = 0,75 M . 0,5 L\\\\molesCH_{3}OH = 0,375 mol

therefore the solution is prepared using 0.5 L of H2O and 0.375 moles of CH3OH,  resulting in a concentration of 0,75M

5 0
3 years ago
Explain how the understanding of atomic emission spectrum led to development of the atomic theory? ( 4 points)
-Dominant- [34]
Well, all of this we owe it to Bohr who analyzed the atomic emission spectrum of hydrogen and he could probe matematically that it was a result of movement of e- from an especific energy level to a lower one. The understanding of levels of energy took to the development of the atomic theory
5 0
3 years ago
Read 2 more answers
At constant pressure, a sample of gas occupies 420 mL at 210 K. What volume does the gas occupy at 250 K?
marissa [1.9K]
V₁ = 420 mL
T₁ = 210 K
V₂ = ?
T₂ = 250 K
(Answer is 500 mL)

5 0
3 years ago
How many moles of H2O will be produced from 26.0 g of H2022<br> Stoichiome
lukranit [14]

Answer:

                       0.7644 moles of H₂O

Explanation:

                    The balance chemical equation is as follow;

                                      2 H₂O₂ → 2 H₂O + O₂

To solve this problem we will first calculate the moles of H₂O₂ as,

                           Moles  =  Mass / M/Mass

                           Moles  =  26.0 g / 34.01 g/mol

                           Moles  =  0.7644 mol

Secondly,

According to equation,

                      2 moles of H₂O₂ produces  =  2 moles of H₂O

Hence,

                0.7644 mol of H₂O₂ will produce  =  X moles of H₂O

Solving for X,

                        X  =  2 mol × 0.7644 mol / 2 mol

                       X =  0.7644 moles of H₂O

5 0
3 years ago
Aspirin is prepared by reacting salicylic acid with excess ethanoic anhydride. in an experiment, 50.05 g of salicylic acid was c
expeople1 [14]
The balanced reaction would be written as:
<span>
C7H6O3 + C4H6O3--->C9H8O4 + HC2H3O2

To determine the percent yield, we need to first determine the theoretical yield if the reaction were to proceed completely. Then, we divide the actual yield that is given to the theoretical yield times 100 percent. The limiting reactant from the reaction would be salicylic acid. We do as follows: 

<span>Theoretical yield: 50.05 g C7H6O3 ( 1 mol / 138.21 g ) ( 1 mol C9H8O4 / 1 mol C7H6O3 ) ( 180.157 g / mol ) = 65.24 g C9H8O4 should be produced

Percent yield = 55.45 / 65.24 x 100 = 84.99%
<span>
Therefore, the percent yield for the given amount of salicylic acid is 84.99%
</span></span></span><span><span><span>
</span></span></span>
5 0
3 years ago
Other questions:
  • What is a hydrocarbon? A. A molecule containing only carbon and oxygen B. A molecule containing only carbon as a solid C. A mole
    7·1 answer
  • PLEASE HELP!!! 890 g of reactant A completely reacts with 120 g of reactant B to form two products. If product A has a mass of 9
    11·1 answer
  • At room temperature, a melting solid produces a whitish liquid. A laser beam shined through the liquid is unaffected and produce
    15·1 answer
  • Complete the unit conversion by entering the correct numbers <br> A=<br> B=<br> C=
    6·1 answer
  • What is 1.5 x 10^3 in standard notation
    13·1 answer
  • PLEASE HELP ME TAKE SOO LONG! (ima fail this test!) its a study guide!
    9·1 answer
  • Pls help me 20 points ty
    11·2 answers
  • You have 300,000 atoms of a radioactive substance. After 3 half-lives have past, how many atoms remain? Remember that you cannot
    8·1 answer
  • In an experiment magnesium ribbon was heated in air. The product was found to be heavier than the original ribbon. Potassium man
    15·1 answer
  • Can someone help me i will give 100 points
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!