Question

1. respuestas múltiples 1 punto

which phase(s) of matter has variable shape?
gas
solid
liquid

1. fórmula 1 punto

if 5.0 l of oxygen at 881 mm hg are compressed to 450 mm hg at constant temperature. what is the new volume, in l? round to 1 decimal place
respuesta

1. decisión múltiple 1 punto

which of the following describes gas pressure?
the number of particles
the average kinetic energy of the particles
the collisions of the particles with the walls of the container
the size of the container

Explanation:

1.

Gases have variable shape as they take the shape of their container. Solids have a fixed shape and liquids take the shape of the part of the container they occupy but are more fixed - shaped compared to gases.

Step1: Identify the formula

Boyle's law is $P_1V_1 = P_2V_2$, where $P_1$ and $V_1$ are initial pressure and volume, and $P_2$ and $V_2$ are final pressure and volume.

Step2: Substitute the given values

We have $P_1 = 881$ mm Hg, $V_1=5.0$ L, $P_2 = 450$ mm Hg. We need to find $V_2$. Rearranging the formula for $V_2$ gives $V_2=\frac{P_1V_1}{P_2}$.

Step3: Calculate the new volume

$V_2=\frac{881\times5.0}{450}=\frac{4405}{450}\approx9.8$ L

Gas pressure is caused by the collisions of gas - particles with the walls of the container. The number of particles affects the amount of pressure but is not the definition of pressure. The average kinetic energy of particles is related to temperature. The size of the container affects the pressure but is not what pressure is.

Answer:

Gas

2.