A Laboratory Vacuum Pump Can Reduce the Pressure in a Chamber

question 33

Multiple Choice

A laboratory vacuum pump can reduce the pressure in a chamber to $1.0 \times 10 ^ { - 7 } \mathrm {~Pa}$ If the volume of the chamber is $0.500 m ^ { 3 }$ and the temperature is $27 ^ { \circ } \mathrm { C }$ how many molecules are left inside chamber? $\left( N _ { \mathrm { A } } = 6.022 \times 10 ^ { 23 } \mathrm { molecules } / \mathrm { mol } , R = 8.31 \mathrm {~J} / \mathrm { mol } \cdot \mathrm { K } \right)$

• A) \(2.4 \times 10 ^ { 13 }\)
• B) \(1.2 \times 10 ^ { 14 }\)
• C) \(1.2 \times 10^{13}\)
• D) \(1.2 \times 10^{12}\)
• E) \(2.4 \times 10 ^ { 12 }\)

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Definitions:

Gomphoses

A type of fibrous joint that is a peg-in-socket, such as the joint between a tooth and its socket in the jaw.

Hip And Shoulder

Joints that connect the limbs to the torso; the hip being the articulation between the pelvis and the femur, and the shoulder connecting the upper arm to the torso.

Gliding Motion

A smooth movement where surfaces slide past one another, typical in some types of joints like the carpals of the wrist.

Plane Joint

A type of synovial joint which allows only sliding or gliding movements where the articular surfaces are flat.