Answer : The correct option is, pressure.
Explanation :
The ideal gas equation is,

where,
P = pressure of the gas
V = volume of the gas
n = number of moles of gas
T = temperature of the gas
R = gas constant
The value of 'R' has several different values which are :




That means, the value of 'R' is different due the change in the pressure value and all the variables (temperature, volume and moles) are constant.
Hence, the correct option is, pressure.
Answer:
Dalton's atomic theory proposed that all matter was composed of atoms, indivisible and indestructible building blocks. While all atoms of an element were identical, different elements had atoms of differing size and mass.
Substances that have a define size and shape and vibrating particles that are close together are called Solid.
Explanation:
There are three states of matter - solid, liquid and gas.
Lets talk about solid state in detail.
In solid particles are closely packed and so they have very less or no space to move which results in vibrating particles. This results in solid substances having a fixed shape and volume.
The particles have very little space in between them, so it is not easy to compress solid.
There is no free space for particles to slide over each other, which does not allow solids to flow.
Also, particles in solid have a regular arrangement, they are not randomly packed.
The answer is Rubidium (Rb)