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BaLLatris [955]
3 years ago
15

Which pair of elements is in the same period? (Check ALL that apply) *

Chemistry
1 answer:
stira [4]3 years ago
3 0

Answer:

D and R are in the same period

Explanation:

remember groups are vertical and periods are horizontal!

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The decomposition of dinitrogen pentaoxide has an activation energy of 102 kJ/mol and ΔH°rxn = + 55 kJ/mol. What is the activati
ahrayia [7]

<u>Answer:</u> The activation energy of the reverse reaction is 47 kJ/mol

<u>Explanation:</u>

The chemical equation for the decomposition of dinitrogen pentaoxide follows:

N_2O_5\rightleftharpoons 2NO_2+\frac{1}{2}O_2

We are given:

Activation energy of the above reaction (forward reaction) = 102 kJ/mol

Enthalpy of the reaction = +55 kJ/mol

As, the enthalpy of the reaction is positive, the reaction is said to be endothermic in nature.

To calculate the activation energy for the reverse reaction, we use the equation:

E_a_{\text{(forward)}}=E_a_{\text{(backward)}}+|\Delta H|

where,

E_a_{\text{(forward)}} = Activation energy of the forward reaction = 102 kJ/mol

E_a_{\text{(backward)}} = Activation energy of the backward reaction = ?

\Delta H = Enthalpy of the reaction = +55 kJ/mol

Putting values in above equation, we get:

102=E_a_{\text{(backward)}}+55\\\\E_a_{\text{(backward)}}=(102-55)=+47kJ/mol

Hence, the activation energy of the reverse reaction is 47 kJ/mol

3 0
3 years ago
What happens when energy is transferred through a wave?
Alexeev081 [22]

In electromagnetic waves, energy is transferred through vibrations of electric and magnetic fields. In sound waves, energy is transferred through vibration of air particles or particles of a solid through which the sound travels.

5 0
3 years ago
The mass number of 3 isotopes of magnesium are 24,25,26.what is the mass number of the most abundant isotope of magnesium.​
Anarel [89]

Answer:

24.4 amu or g/mole

Explanation:

24 x 0.790 = 19.0 amu

25 x 0.100 = 2.50 amu

26 x 0.110 = 2.86 amu

(Because of the 19.0, the sig figs go only to the 1/10 decimal place)

19.0 + 2.5 + 2.9 = 24.4 amu or g/mole

7 0
3 years ago
5. List four examples of neutralization reactions and four for acid-base reactions. You can revisit last week's lesson #
garik1379 [7]

Answer:

Reacciones de neutralización

Mg(OH)2

NaHCO3

Bicarbonato de sodio

Cloruro de sodio

Reacciones acido base

HCl + NaOH → NaCl + H2O.

H2SO4 + 2 NaOH → Na2SO4 + H2O.

HCl + NH3 → NH4Cl + H2O.

HCN + NaOH → NaCN + H2O.

Explanation:

7 0
3 years ago
Which species is the conjugate acid of the hemiacetal formed by reaction of benzaldehyde with methanol containing a trace of aci
fiasKO [112]

Answer:

Sulphuric acid is the on

Explanation:

think so

3 0
3 years ago
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