Acylinder fitted with a movable piston and filled with a gas has a volume of 16.44 liters at 22.4°c when the applied pressure is 772.2 torr.
the temperature of the oil bath surrounding the piston was increased to 184.4°c, and the pressure on the piston was changed. careful measurement now gave a value of 39.03 liters for the new volume.

what is the final pressure in the cylinder, expressed in torr?

a) 494.0 torr

b) 503.6 torr

c) 1184 torr

d) 1207 torr

e) 6295 torr

with explanation .

b) 503.6 torr

Explanation:

Given data

We can find the final pressure applying the combined gas law.

when 25.0 ml of 0.700 mol/l naoh was mixed in a calorimeter with 25.0 ml of 0.700 mol/l hcl, both initially at 20.0 °c, the temperature increased to 22.1 °c. the heat capacity of the calorimeter is 279 j/°c.

the equation for the reaction is:

naoh + hcl → nacl + h₂o

moles of hcl = 0.0250 l hcl ×

0.700

mol hcl

1 l hcl = 0.0175 mol hcl

volume of solution = (25.0 + 25.0) ml = 50.0 ml

mass of solution = 50.0 ml soln ×

1.00

ml soln

= 50.0 g soln

δt=t2-t1

= (22.1 – 20.0) °c = 2.1 °c

the heats involved are

heat from neutralization + heat to warm solution + heat to warm calorimeter = 0

q1+q2+q3=0

nδh+mcδt+cδt=0

0.0175 mol ×

δh

+ 50.0 g × 4.184 j·g⁻¹°c⁻¹ × 2.1 °c + 279 j°c⁻¹ × 2.1 °c = 0

0.0175 mol ×

δh

+ 439.32 j + 585.9 j = 0

0.0175 mol ×

δh

= -1025.22 j

δh=1025.22j0.0175 mol= -58 600 j/mol = -58.6 kj/mol

lol for the pointsss