Answers
Whereas, the system under study is absorbing heat that is produced during the reaction. So if ΔH is found to be positive then it can be called as endothermic reaction.
The enthalpy change of the reaction indicates that it is an endothermic process.
FURTHER EXPLANATION
Enthalpy (ΔH) is the amount of heat absorbed or released in a reaction. It is based on the amount of energy needed to break the bonds and the energy released during bond formation. Enthalpy change is the difference in the enthalpy of the reactants and the products. The positive or negative sign for an enthalpy value indicates the direction of the heat flow: a positive ΔH indicates that the reaction is endothermic while a negative value for ΔH means that the reaction is exothermic.
Endothermic Reactions
Endothermic reactions are reactions that absorb heat from the surroundings to the system. This is the case when more energy is absorbed to break the bonds than is released to form the bonds. Endothermic reactions can be identified in the lab by observing if the reaction vessel becomes cooler as the reaction proceeds.
Exothermic Reactions
When the amount of energy released during bond formation is greater than the amount of energy absorbed during bond breaking, a net release of energy to the surroundings takes place and the reaction is exothermic. Exothermic reactions can be identified when the reaction vessel becomes hot as the reaction progresses.
LEARN MORE
- Heat capacity brainly.com/question/12976104
- Equilibrium brainly.com/question/12983923
- Gibbs Free Energy brainly.com/question/12979420
Keywords: Endothermic, Exothermic, Enthalpy
Related Questions
Write the net ionic equation for the precipitation reaction that occurs when aqueous solutions of potassium sulfide and chromium(II) nitrate are combined. Use the pull-down boxes to specify states such as (aq) or (s). If a box is not needed leave it blank. 2Cr^3+ + 3S^2- (aq) + + rightarrow Cr_2S_4 (s) +
What other reactions is taking place?
when the pressure that a gas exerts on a sealed container changes from 3.74 atm to ____ atm, the temperature changes from 394 K to 789 K
Write the full ionic equation and net ionic equation for sodium dihydrogen phosphate + calcium carbonate, sodium oxilate + calclium carbonate, and sodium hydrogen phosphate + calcium carbonate
Answers
Answer:
two atoms of oxygen. For H2O, there is one atom of oxygen and two atoms of hydrogen.
(B) HF, pKa = 3.46
(C) HClO, pKa = 7.54
(D) HCN, pKa = 9.31
(E) HClO2, pKa = 1.96
Answers
Answer:
The buffer of pH 8.10 will be formed by the HClO having pKa value of 7.54.
Explanation:
Buffer is defined as the substance that can withstand the changes in the solution due to addition of acid or base. Buffer acts to neutralize the small amounts of acids or base when added.
Buffer is composed of two parts:
A weak acid and its conjugate base and a weak base with its conjugate acid.
According to the Bronsted-Lowry theory,acids are the substances that release , whereas the substances that accept bases.
Similarly, when an acid loses a proton ()
, it is converted into the conjugate base, such that the conjugate acid-base pair of HClO is
.
The buffer range for a substance is either one unit more or one unit less than the pKa value of the given substance. Thus, to obtain the pH value of 8.10, the acid with pKa value of 7.54 will be selected. The pH range of will have the buffer range between 6.54 and 8.54. Thus, pH of 8.10 will be formed by
Hence, rest of the options are incorrect because the buffer range for given acids will not be close the given value of pH as 8.10.
For Further Reference:
Answer:
(C) HClO, pKa = 7.54
Explanation:
A buffer is a solution that can resist abrupt changes in pH when acids or bases are added. It is formed by two components:
- A weak acid and its conjugate base.
- A weak base and its conjugateacid.
In this case, acid and base are defined according to Bronsted-Löwry theory, which states that acids are substances that release H⁺ and bases are substances that accept H⁺. Therefore, when an acid loses an H⁺ transforms into its conjugated base. For example, HF/F⁻ is a conjugate acid-base pair.
In buffers, when an acid is added, it reacts with the base to diminish its amount:
F⁻ + H⁺ ⇄ HF
Also in buffers, when a base is added, it reacts with the acid to diminish its amount:
HF + OH⁻ = F⁻ + H₂O
The optimum pH range of work of a buffer system (known as buffer range) is between 1 unit less and 1 unit more of pH than its pKa.
So, the buffer formed by HClO/ClO⁻ works optimally in the pH range 6.54-8.54. Since pH = 8.10 is in that interval, this would be the optimal choice.
Answers
−1
Morality of Ba(OH)
2=0.120mol/L2E6H5COOH+Ba(OH) 2→2H2+Ba(C6H5COO) 2
From the given Molar mass, we find the number of moles of Benzoic acid and Barium
hydrocide.
Moles of Benzoic acid = MolarMass
GivenMass= 122.10.2=0.00163 Moles
Moles of Ba(OH) 2= 20.00163=0.000815
Now, Morality of Ba(OH)
2= LitreofSolutionmolesofsolute=0.120M is required 1 Litre,
So 0.000815M is required in
0.1201 ×0.000815 =0.00679=6.
Answers
Answers
Answer:
0.01454 grams of oxygen is present per kilogram of human muscle.
0.1454 grams of oxygen is present per kilogram of sperm whale muscle.
Explanation:
Given : The myoglobin is fully saturated with oxygen gas.
Moles of myoglobin = Moles of oxygen gas
Molecular mass of myoglobin = 17,600 g/mol
(assumed same fro whale and human )
Myoglobin content in humans = 8 g/kg
Mole of molyoglobin in human muscles per kg :
Mass of oxygen present in per kg of human muscle:
Moles of oxygen gas × 32g/mol :
g/kg of human muscle
Myoglobin content in whales= 80 g/kg
Mole of molyoglobin in whale muscles per kg :
Moles of myoglobin = Moles of oxygen gas
Mass of oxygen present in per kg of sperm whale muscle:
Moles of oxygen gas × 32g/mol :
g/kg of whale muscle
Answers
Answer and Explanation: Sample A is a mixture. Solubility is characteristics of each substance, which means a substance can be distinguished from other substances and can be useful to separate mixtures.
In Sample A, when is added different volumes of water, the resulting powder has different mass. This means there are more than one substance forming the yellow cube. Therefore, sample A is a mixture.
Sample B is a puresubstance. Each substance has its own melting point. Whe na pure substance reaches its melting point, temperature is constant until all of that substance is melted. In sample B, temperature is stable at 66.2°C and then, after all the powder is melted, it rises again. Therefore, sample B is a pure substance.
Final answer:
Sample A is a mixture based on the experiment result, while the nature of Sample B is inconclusive.
Explanation:
The result of the experiment with sample A indicates that it is a mixture. When the solid yellow cube is put into water, it collapses into a small pile of orange powder. The mass of the powder that is left over depends on the amount of water used. This suggests that the cube is composed of different substances that can be separated by filtration.
On the other hand, the result of the experiment with sample B is inconclusive, so we can't decide whether it is a pure substance or a mixture. Heating the coarse grey powder causes it to melt at a constant temperature, but there is a temperature increase after the last of the powder melts. This could indicate that the powder is a pure substance with a melting point range, or it could suggest the presence of impurities.
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