Answer:
option C. Addition of protons to the atomic nucleus.
Explanation:
Elements are fundamentally made up of atoms. Atoms in turn has three sub particles.
These particles are; neutrons, electrons and protons.
The sub particles responsible for the mass of an atoms is basically the protons and neutrons. Going through the options;
The correct option is option C. Addition of protons to the atomic nucleus.
Based on the data provided;
- number of moles of helium gas is 1.25 moles
- pressure at peak temperature is 259.3 kPa
- internal pressure is above 256 kPa, therefore, the balloon will burst.
- pressure should be reduced to a value less than 256 kPa by reducing the temperature
<h3>What is the ideal has equation?</h3>
The ideal gas equation relatesthe pressure, volume, moles and temperature of a gas.
The moles of helium gas is calculated using the Ideal gas equation:
n is the number of moles of gas
R is molar gas constant = 8.314 L⋅kPa/Kmol
P is pressure = 239 kPa
T is temperature = 21°C = 294 K
V is volume = 12.8 L
Therefore;
n = PV/RT
n = 239 × 12.8 / 8.314 × 294
n = 1.25 moles
The number of moles of helium gas is 1.25 moles
At peak temperature, T = 46°C = 319 K
Using P1/T1 = P2/T2
P2 = P1T2/T1
P2 = 239 × 319/294
P2 = 259.3 kPa
The pressure at peak temperature is 259.3 kPa
At 42°C, T = 315 K
Using P1/T1 = P2/T2
P2 = P1T2/T1
P2 = 239 × 315/294
P2 = 256.07 kPa
Since the internal pressure is above 256 kPa, the balloon will burst.
The pressure should be reduced to a value less than 256 kPa by reducing the temperature.
Learn more about gas ideal gas equation at: brainly.com/question/12873752
Ionic bonds are forces that hold together electrostatic forces of attractions between oppositely charged ions. Ionic bonds have an electronegativity difference greater than or equal to 2. Covalent bonds have an electronegativity difference that is less than 2.
Answer : The correct expression will be:

Explanation :
The chemical reactions are :
(1)

(2)

The final chemical reaction is :

Now we have to calculate the value of
for the final reaction.
Now equation 1 is multiply by 2 and then add both the reaction we get the value of 'K'.
If the equation is multiplied by a factor of '2', the equilibrium constant will be the square of the equilibrium constant of initial reaction.
If the two equations are added then equilibrium constant will be multiplied.
Thus, the value of 'K' will be:

Cations from smallest to largest
Li⁺ ,Na⁺, K⁺ (from Periodic Table, the bigger number of period, the bigger size, of atom, so the bigger size of cation)
1) LiF smaller cation then KF
1,036 <span>853
</span><span>The lattice energy increases as cations get smaller, as shown by LiF and KF.
</span><span>I think this one should be correct answer, because the compared substances have also the same anion, and we can compare cations in them.
2) The same cation Li , so wrong statement.
3)</span>The same cation Na , so wrong statement.
4) NaCl smaller cation then KF
786 853