B. 3.77 L is the new volume occupied by the gas.
<u>Explanation:</u>
As per Avogadro's law, which states that if the pressure and temperature held constant, then an equal volume of the gases will occupy an equal number of molecules. It can be written as,
Here, V1, volume of the helium gas = 2.9 L
V2, volume of the additional helium gas in the balloon = ?
n1, moles of helium gas = 0.150 mol
n2, number of moles of additional helium gas = 0.150 + 0.0450 = 0.195 mol
We have to rearrange the equation for V2 as,
V2 = 
Now Plugin the values as,
V2 = 
= 3.77 L
So the new volume of the balloon is 3.77 L.
Answer:- 
Explanations:- In reduction the electrons are accepted and so they are written on the reactant side. When an atom accepts electrons then it forms anion. Chlorine has 7 valence electrons and it needs one more electron to complete it's octet. Since, dichlorine has two Cl atoms and each Cl atom needs one more electron to complete it's octet, two electrons are accepted by dichorine to make aqueous chloride ion. For balancing the equation, there would be two chloride ions as the reactant side has two chlorine atoms.
JJ Thomson discovered electrons using the cathode ray. Electrons are negatively charged particles that orbit around the nucleus of an atom. Finding out that there was a negative charge to balance out the positive charge. This later helped develop Hund's Rule and the Pauli Exclusion Principle.
