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monitta
3 years ago
6

An exothermic reaction has a positive enthalpy (heat) of reaction.(T/F)

Chemistry
2 answers:
mestny [16]3 years ago
5 0

Answer:

True.

Explanation:

An exothermic reaction has a positive enthalpy (heat) of reaction. However, it can be negative in some circumstances.

Temka [501]3 years ago
4 0

Answer:

True.

Explanation:

True, An exothermic reaction has a positive enthalpy (heat) of reaction.

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Another name for a "oxidation-reduction" reaction is
anzhelika [568]
Redox (red for reduction and ox for oxidation)
8 0
3 years ago
25 points please help
maxonik [38]

Answer : Option (A) Accelerator 2 model has the lowest percentage of energy lost as waste.

Solution : Given,

For Accelerator 1 model,

Input energy = 2078.3 J

Wasted energy = 663.1 J

Output energy = 1415.2 J

For Accelerator 2 model,

Input energy = 7690.0 J

Wasted energy = 2337.5 J

Output energy = 5353.5 J

For Accelerator 3 model,

Input energy = 4061.9 J

Wasted energy = 2259.6 J

Output energy = 1802.3 J

Formula used for lowest percentage of energy lost as waste is:

% energy lost as waste = (Total energy wasted / Total input energy )  ×  100

For Accelerator 1 model,

% energy lost as waste = \frac{663.1}{2078.3}\times100 = 31.90%

For Accelerator 2 model,

% energy lost as waste = \frac{2337.5}{7690.0}\times100 = 30.39%

For Accelerator 3 model,

% energy lost as waste = \frac{2259.6}{4061.9}\times100 = 55.62%

So, we conclude that the Accelerator 2 model has the lowest percentage of energy lost as waste.



6 0
3 years ago
2 NO + O22 NO2 is second order in NO and first order in O2. Complete the rate law for this reaction in the box below. Use the fo
riadik2000 [5.3K]

Answer : The value of rate of reaction is 1.35\times 10^{-8}Ms^{-1}

Explanation :

Rate law : It is defined as the expression which expresses the rate of the reaction in terms of molar concentration of the reactants with each term raised to the power their stoichiometric coefficient of that reactant in the balanced chemical equation.

The given chemical equation is:

2NO+O_2\rightarrow 2NO_2

Rate law expression for the reaction is:

\text{Rate}=k[NO]^a[O_2]^b

As per question,

a = order with respect to NO  = 2

b = order with respect to O_2 = 1

Thus, the rate law becomes:

\text{Rate}=k[NO]^2[O_2]^1

Now, calculating the value of rate of reaction by using the rate law expression.

Given :

k = rate constant = 9.87\times 10^3M^{-2}s^{-1}

[NO] = concentration of NO = 7.86\times 10^{-3}M

[O_2] = concentration of O_2= 2.21\times 10^{-3}M

Now put all the given values in the above expression, we get:

\text{Rate}=(9.87\times 10^3M^{-2}s^{-1})\times (7.86\times 10^{-3}M)^2\times (2.21\times 10^{-3}M)^1

\text{Rate}=1.35\times 10^{-8}Ms^{-1}

Hence, the value of rate of reaction is 1.35\times 10^{-8}Ms^{-1}

7 0
3 years ago
Ionic bonds are ___________ than covalent bonds and are ___________ common in cells.
sammy [17]

Answer:

Ionic bonds are stronger than covalent bonds

8 0
1 year ago
Increasing the pressure on a gas _____ the volume the gas occupies
BlackZzzverrR [31]
This should increase the  volume.

3 0
3 years ago
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