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
MrRa [10]
4 years ago
12

Describe the ways you can know that a chemical reaction has occurred.

Chemistry
2 answers:
Bad White [126]4 years ago
8 0
Signs that a chemical reaction is occurring are: 1. change in color 2. change in odor 3. change in pH, as in changes from acid to base or base to acid
Pachacha [2.7K]4 years ago
6 0

The color can change  so can the PH  and oder.

You might be interested in
Calculate the mass percent of HOCH 2CH 2OH in a solution made by dissolving 3.2 g of HOCH 2CH 2OH in 43.5g of water.
grin007 [14]

Answer:

\%m/m=6.85\%

Explanation:

Hello,

In this case, we are asked to compute the by mass percent for the given 3.2 g of ethylene glycol in 43.5 g of water. In such a way, since the by mass percent is computed as follows:

\%m/m=\frac{m_{solute}}{m_{solute}+m_{solvent}} *100\%

Whereas the solute is the ethylene glycol and the solvent the water, therefore we obtain:

\%m/m=\frac{3.2g}{3.2g+43.5g} *100\%\\\\\%m/m=6.85\%

Best regards.

5 0
3 years ago
Explain why beryllium looses electrons while ionic bonds,while Sulfur gains electrons.
balandron [24]

Answer:

Since Beryllium has a larger atomic radius than Sulphur its electrons are not strongly attracted to the nucleus hence lost easily. But Sulphur has a small atomic radius hence electrons are more closely attracted to the nucleus.

3 0
2 years ago
What properties are associated with metals (grade 9 science)
quester [9]

Answer:

metals can be magnetic.

Explanation:

certain types of metals are magnetic.

5 0
3 years ago
(7th grade science question)
Akimi4 [234]
The most accurate way to measure a dry ingredient like flour, sugar or chocolate chips is in terms of its weight, which is measured in regular ounces.
7 0
3 years ago
La aspirina se prepara haciendo reaccionar ácido salicílico con exceso de anhídrido etanoico. En un experimento, 50.05 g de ácid
Tanya [424]

La aspirina se prepara haciendo reaccionar ácido salicílico con exceso de anhídrido etanoico. En un experimento, 50.05 g de ácido salicílico se convirtieron en 55.45 g de aspirina. ¿Cuál fue el porcentaje de rendimiento?

<em>In English:</em>

Aspirin is prepared by reacting salicylic acid with excess ethanoic anhydride. In one experiment, 50.05 g of salicylic acid was converted to 55.45 g of aspirin. What was the yield percentage?

Answer:

el rendimiento porcentual para la cantidad dada de ácido salicílico es 84.99 %

<em>In English:</em>

<em>the percent yield for the given amount of salicylic acid is </em><em>84.99%</em>

<em></em>

Explanation:

La ecuación química equilibrada para la reacción se puede escribir como:

C₇H₆O₃ + C₄H₆O₃    →    C₉H₈O₄ + HC₂H₃O₂

Para la reacción mostrada arriba; El reactivo limitante de la reacción es el ácido salicílico. Ahora; calcular el porcentaje de rendimiento; se espera que primero determinemos el rendimiento teórico de la reacción.

Entonces; la fórmula para calcular el porcentaje de rendimiento: \mathbf {= \frac{actual \ yield }{theoretical \ yield } *100 }  

El rendimiento teórico se determina de la siguiente manera:

50.05 g * 1 mol / 138.21 g / mol de C₇H₆O₃ * 1 mol de C₉H₈O₄ / 1 mol de C₇H₆O₃ * 180.157 g / mol de C₉H₈O₄ = 65.24 g de C₉H₈O₄

Porcentaje de rendimiento \mathbf {= \frac{55.45 }{65.24 } *100 }

Porcentaje de rendimiento = 84.99%

Por lo tanto, el porcentaje de rendimiento para la cantidad dada de ácido salicílico es 84.99%

<em>In English:</em>

<em>The balanced chemical eqaution for the reaction can be written as:</em>

<em>C₇H₆O₃ + C₄H₆O₃    →    C₉H₈O₄ + HC₂H₃O₂</em>

<em>For the reaction shown above;  The limiting reactant from the reaction is  salicylic acid. Now; to calculate the percentage yield ; we are expected to first determine the theoretical yield of the reaction. </em>

<em>So; the formula for calculating the percentage yield </em>\mathbf {= \frac{actual \ yield }{theoretical \ yield } *100 }<em>  </em>

<em />

<em>The theoretical yield is determined as follows:</em>

<em>50.05 g * 1 mol/ 138.21 g/mol of C₇H₆O₃ * 1 mol of C₉H₈O₄/ 1 mol of C₇H₆O₃ * 180.157 g/mol of C₉H₈O₄ = 65.24 g of C₉H₈O₄ is produced</em>

<em />

<em>Percentage yield </em>\mathbf {= \frac{55.45 }{65.24 } *100 }<em />

<em>Percentage yield = 84.99%</em>

<em />

<em>Thus, the percent yield for the given amount of salicylic acid is </em><em>84.99%</em>

7 0
4 years ago
Other questions:
  • A solution contains 225 g of sodium chloride, NaCl, dissolved in enough water to make a 0.25 L of solution. What is the molarity
    12·1 answer
  • What is the empirical formula for a compound which contains 0.0134 g of iron, 0.00769 g of sulfur and 0.0115 g of oxygen
    5·1 answer
  • Hydrogen is unique among the elements because ________. 1. It is not really a member of any particular group. 2. Its electron is
    7·1 answer
  • What might happen to the sickle-cell mutation if malaria in Africa were eliminated?
    13·1 answer
  • What happened when you closed your hand around the sponge?
    5·1 answer
  • Write the ΔH system for each of the following changes in physical state
    6·1 answer
  • What can destroy buffer solution?
    13·1 answer
  • why is often necessary to follow extensive purification procedures in the isolation of organic compounds?​
    13·1 answer
  • Why is a neutral solution neutral?
    15·2 answers
  • Calculate the molarity of Kool-Aid if each pack contains 4.5 g of powder, the molar mass of the Kool-aid is 90 g/mol, and it mak
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!