Benzoyl chloride, c6h5cocl, reacts with water to form benzoic acid, c6h5cooh, and hydrochloric acid. this first-order reaction is 25% complete after 26 s. how much longer would one have to wait in order to obtain 99% conversion of benzoyl chloride to benzoic acid? 180 s210 s290 s390 s420 s

The time required for the conversion of benzoyl chloride to benzoic acid is 390 seconds.

Explanation:

The expression for the rate law of first order kinetics is given as:

     ......(1)

where,

= initial mass of isotope = 100 g

N = mass of the parent isotope left after the time = 100 - 25 = 75 g

t = time taken = 26 s

k = rate constant = ?

Putting values in above equation, we get:

Now, we need to find the time when 99 % of the reaction is complete. Using equation 1 again, we get:

= initial mass of isotope = 100 g

N = mass of the parent isotope left after the time = 100 - 99 = 1 g

t = time taken = ? s

k = rate constant =

Putting values in above equation, we get:

Time required for the conversion of benzoyl chloride to benzoic acid = 416 - 26 = 390 s

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

im pretty sure its b