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
lisabon 2012 [21]
3 years ago
14

How can you tell a chemical change has happened?

Chemistry
2 answers:
Paladinen [302]3 years ago
4 0

Answer:

How can I tell if a chemical reaction is occurring? A chemical reaction is usually accompanied by easily observed physical effects, such as the emission of heat and light, the formation of a precipitate, the evolution of gas, or a color change.

Explanation:

Kisachek [45]3 years ago
3 0

Answer:

You can tell when a chemical change has happened when the chemical changes in appearance such as color or physical state.

Explanation:

If a change happens it can change in any way shape or form.

You might be interested in
1.00 L of a gas at STP is compressed to 473mL. What is the new pressure of gas?
Ratling [72]

Hello!

1.00 L of a gas at STP is compressed to 473 mL. What is the new pressure of gas?

  • <u><em>We have the following data:</em></u>

Vo (initial volume) = 1.00 L  

V (final volume) = 473 mL → 0.473 L  

Po (initial pressure) = 1 atm (pressure exerted by the atmosphere - in STP)  

P (final pressure) = ? (in atm)

  • <u><em>We have an isothermal transformation, that is, its temperature remains constant, if the volume of the gas in the container decreases, so its pressure increases. Applying the data to the equation Boyle-Mariotte, we have:</em></u>

P_0*V_0 = P*V

1*1 = P*0.473

1 = 0.473\:P

0.473\:P = 1

P = \dfrac{1}{0.473}

\boxed{\boxed{P \approx 2.11\:atm}}\:\:\:\:\:\:\bf\green{\checkmark}

<u><em>Answer:  </em></u>

<u><em>The new pressure of the gas is 2.11 atm  </em></u>

___________________________________

\bf\blue{I\:Hope\:this\:helps,\:greetings ...\:Dexteright02!}\:\:\ddot{\smile}

3 0
3 years ago
Calculate the mass of 3.4 moles of nitric acid (hno3). explain the process or show your work by including all values used to det
balu736 [363]

Answer:

6.34917360^25g

Explanation:

It's been a while since I've done this type of problem so I'm not making any promises that its right hahaha, but I hope it helps anyway. Please let me know whether I'm right or not!

6 0
1 year ago
26 g of zinc combines with 12.8 g of sulfur. What is the empirical formula of zinc sulfide?
Alisiya [41]
Moles of Zn: 26 / 65 = 0.4
Moles of S: 12.8 / 32 = 0.4

Molar ratio of Zn : S = 1 : 1
Empircal formula: ZnS

The answer is C
7 0
3 years ago
The percent abundance of each isotope tells you how many of each kind of isotope exist in every 100 particles. What does relativ
fiasKO [112]

Answer:

The answer is Relative plenitude alludes to the amount of a specific isotope is available in a given measure of test.  

Explanation:

The 'relative plenitude' of an isotope implies the level of that specific isotope that happens in nature. Most components are comprised of a blend of isotopes. The total of the rates of the particular isotopes must indicate 100%. The relative nuclear mass is the weighted normal of the isotopic masses. The percent plenitude of every sort of sweets reveals to you what number of every sort of Aufbau there are in each 100 CANDIES. Percent wealth is additionally relative plenitude. This is only a method for giving us a photo on which kind exists all the more every now and again.

3 0
3 years ago
10. Isolation of a pure sample of the third product, which has been determined to be an isomer of the major and minor products,
Ymorist [56]

Answer:

Four possible isomers (1–4) for the natural product essramycin. The structure of compound 1 was attributed to essramycin by 1H NMR, 13C NMR, HMBC, HRMS, and IR experiments.

Explanation:

Three synthetic routes were used to prepare all four compounds (Figure 2A). All three reactions utilize 2-(5-amino-4H-1,2,4-triazol-3-yl)-1-phenylethanone (5) as the precursor, whereas each uses different esters (6–8) to construct the pyrimidinone ring. Isomer 1 was prepared by reaction A, which used triazole 5 and ethyl acetoacetate (6) in acetic acid. This was the reaction used in syntheses of essramycin by the Cooper and Moody laboratories.3,4 Reaction B produced compound 2 (minor product) and compound 3 (major product), which were separated chromatographically. This reaction allowed reagent 5 to react with ethyl 3-ethoxy-2-butenoate (7) in the presence of sodium in methanol, under reflux for 24 h. Compound 4 was prepared by reaction C, which was obtained by reflux of 5 and methyl 2-butynoate (8) in n-butanol.

7 0
3 years ago
Other questions:
  • A 211 g sample of barium carbonate, baco3, reacts with a solution of nitric acid to give barium nitrate, carbon dioxide, and wat
    11·1 answer
  • Many pollutants from coal-fired power plants are properly managed today. Which of the following is currently considered to be th
    12·1 answer
  • A lack of sewage structures in overcrowded cities may lead to __________.
    13·2 answers
  • What is the molar mass of a compound if 25.0 g of the compound dissolved in 750. Ml gives a molarity of 0.290 m?
    13·1 answer
  • A common function of proteins and carbohydrates in the plasma membrane is...
    7·1 answer
  • Please help!!
    13·2 answers
  • Round the following number to four figures: 45.4673
    14·2 answers
  • Two spherical objects with a mass of 7.73 kg each are placed at a distance of 1.11 m apart. how many electrons need to leave eac
    7·1 answer
  • Which one of the following is not a mixture?Air,mercury ,milk,cement​
    5·2 answers
  • There are ________ mol of bromide ions in 0.700 L of a 0.400 M solution of AlBr
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!