When placed in a 100mL cube shaped box a substance fills the cube and has a volume of 100 mL. When places in a 50mL tube that same amount of substance fills the tube and thus has a 50mL volume. What is the state of the substance A - plasma B-Liquid C - Solid D - Gas?

There are five states of matter out of which we encounter three states of matter in our day today life

a) gas b) solid and c) liquid

the main difference between the three is of

a) Inter molecular forces of attraction

b) thermal energy

due to this

a) solid has high intermolecular forces and low thermal energy: thus they have fix shape and occupy fix volume

b) liquid has intermediate forces and medium themal energy. Thus they may have fixed volume and but no fix shape

c) gas has weak intermoelcular forces and high thermal energy. thus they have no fixed volume no fix shape

so in the given problem

the state of the substance D - Gas.