Answer:
Explanation:
The question is asking to write the <em>isotopic symbol </em>of the form 
for the <em>sodium isotope with 13 neutrons</em>.
In general, the isotopic symbol in the given form shows:
- The element's chemical symbol: X
- A: mass number of the isotope, written as a superscript to the left of the element's simbol, and
A = number of protons + number of neutrons
- Z: atomic number of the isotope, written as a subscript to the left of the elements's symbol,
Z = number of protons
The atomic symbol of sodium is Na.
The atomic number, or number of protons, is the same for every isotope of the element, and you can find it in any periodic table. Tha atomic number of sodium is 11. Thus:
The mass number is the number of protons plus neutrons, hence:
Now you can write the isotope symbol for the sodium isotope with 13 neutrons:
Answer:
<h3>D energy of motion</h3>
Explanation:
Kinetic energy is the energy present in mass in motion
Answer:
= 100kJ
Explanation:
The reverse reaction's activation energy of a reaction is the activation energy of the forward reaction plus ΔH of the reaction:
Ea of forward reaction =75kJ
∆H = -175 kJ/mol
Ea of reverse reaction = 75 +(-175)
= 100kJ
Note that a reverse reaction is one which can proceed in both direction depending on the conditions.
If an an element has an atomic number of 60, then there would me 60 protons.
Something that helps me is APE.
The atomic number is the same as the number of protons and electrons.
Answer: option D) energy was absorbed and entropy increased.
Explanation:
1) Given balanced equation:
2H₂O (l) + 571.6 kJ → 2 H₂ (g) + O₂(g).
2) Being the energy placed on the side of the reactants means that the energy is used (consumed or absorbed). This is an endothermic reaction.
So, the first part is that energy was absorbed.
3) As for the entropy, it is a measure of the disorder or radomness of the system.
Since, two molecules of liquid water were transformed into three molecules of gas, i.e. more molecules and more kinetic energy, therefore the new state has a greater degree of radomness, is more disordered, and you conclude that the entropy increased.
With that, you have shown that the right option is D) energy was absorbed and increased.
