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
Zina [86]
3 years ago
9

Given x g of a substance that has a molar mass of y g/mol, which operation will give an answer with units of moles?

Chemistry
1 answer:
Kryger [21]3 years ago
6 0

To calculate moles of any \text{x grams} of a subtance, we need to divide the given mass by the molar mass of the substance that is \text{y grams/mol} given as per the question. By simply putting the values of the two masses we will be left with the number of moles of the given substance.

n=\frac{m}{M}

where, n= number of moles of given substance (mol)

m= given mass of the substance (grams)

M= molar mass of the given substance (grams/mol)

You might be interested in
A student dissolves 15.0 g of ammonium chloride(NH4Cl) in 250. 0 g of water in a well-insulated open cup. She then observes the
iren2701 [21]

Answer:  

1) Endothermic.  

2) Q_{rxn}=4435.04J  

3) \Delta _rH=15.8kJ/mol

Explanation:  

Hello there!  

1) In this case, for these calorimetry problems, we can realize that since the temperature decreases the reaction is endothermic because it is absorbing heat from the solution, that is why the temperature goes from 22.00 °C to 16.0°C.  

2) Now, for the total heat released by the reaction, we first need to assume that all of it is released by the solution since it is possible to assume that the calorimeter is perfectly isolated. In such a way, it is also valid to assume that the specific heat of the solution is 4.184 J/(g°C) as it is mostly water, therefore, the heat released by the reaction is:

Q_{rxn}=-(15.0g+250.0g)*4.184\frac{J}{g\°C}(16.0-20.0)\°C\\\\ Q_{rxn}=4435.04J    

3) Finally, since the enthalpy of reaction is calculated by dividing the heat released by the reaction over the moles of the solute, in this case NH4Cl, we proceed as follows:

\Delta _rH=\frac{ Q_{rxn}}{n}\\\\\Delta _rH= \frac{ 4435.04J}{15.0g*\frac{1mol}{53.49g} } *\frac{1kJ}{1000J} \\\\\Delta _rH=15.8kJ/mol

Best regards!  

Best regards!

4 0
3 years ago
How to know the elements amount of charge amount​
MrRa [10]

For a single atom, the charge is the number of protons minus the number of electrons

6 0
2 years ago
Draw the major organic substitution product(s) for (2R,3S)-2-bromo-3-methylpentane reacting with the given nucleophile. Indicate
Andrew [12]

Answer:

(2R,3S)-2-ethoxy-3-methylpentane

and

(2S,3S)-2-ethoxy-3-methylpentane

Explanation:

For this case, we will have  CH_3CH_2O^- as nucleophile. Also, this compound is also in excess. So, we will have as solvent CH_3CH_2OH a protic solvent. Therefore the Sn1 reaction would be favored.

The first step would be the carbocation formation followed by the attack of the nucleophile. In this case both isomers would be produced: R and S (see figure).

7 0
2 years ago
How many moles of water are produced from 40.0 g of C2H6?
inn [45]

Answer:

4 moles of water

Explanation:

this is a combustion reaction, so the balanced equation is: 2C2H6 + 7O2 → 4CO2 + 6H2O.

the molar mass of C2H6 is 30.07g, so 40.0 g of C2H6 is 1.33 moles of C2H6.

mole ratio of H2O to C2H6 is 6/2, or 3.

1.33 moles C2H6 * 3 moles H2O/1 mole C2H6 = 4 moles H2O

4 0
2 years ago
A 35.66g sample of copper is heated using 600j of energy. if the original temperature of the copper is 85C what is its final tem
ira [324]

This problem is providing the mass, energy, initial temperature and specific heat of a sample of copper that is required to calculate the final temperature.

Thus, we recall the general heat equation:

Q=mC(T_f-T_i)\\

Which has to be solved for the final temperature, T_f as follows:

T_f=T_i+\frac{Q}{mC}

Finally, we plug in the numbers to obtain:

T_f=85\°C+\frac{600J}{35.66g*0.38\frac{J}{g\°C} } \\\\T_f=129.3\°C

However, this result is not given in the choices.

Learn more:

  • brainly.com/question/14383794
8 0
2 years ago
Other questions:
  • What volume of a substance will have a mass exactly 750 g if the specific gravity of the substance is 12.2
    7·1 answer
  • Write the number of atoms of each element found in one unit of the compound:
    8·2 answers
  • MORE HELP ANOTHER 20 POINTS AND BRAINLIEST
    13·1 answer
  • Natural resources like oil and copper metal take a very long time to form. Because of this, they are known as A) fossil fuels. B
    10·2 answers
  • C. Which molecule is not linear?<br> a H₂O<br> b. CO₂<br> c. N₂<br> d. Cl₂
    9·1 answer
  • Someone please help will mark as brainliest
    15·1 answer
  • Cutting, melting, bending, or crushing are examples of what kind of change?
    12·2 answers
  • Which set of statements best explains the relationship between the parts of the respiratory system?
    6·1 answer
  • ice _______________ - a collective term for several mechanical weathering processes induced by stresses created by the freezing
    5·1 answer
  • When compared to the standard hydrogen electrode, zinc has a reduction potential of -0.762 volts and copper a reduction potentia
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!