Taking a Route into Flow and Onto Scale · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

From flask to flow

Science · Chemistry · ages 23-24
Name ______________________   Date ____________

  1. What changes when you move a step from flask to reactor?

    • Only the colour of the vessel
    • Mixing, heat removal, and reacting time
    • Nothing but the label on the door

  2. Which step of a route usually resists scale-up?

    • The fast step that gives off heat
    • The slowest ice-cold step
    • The step with the cheapest reagents

  3. In flow, only a trace of unstable intermediate exists at any moment.

    Circle one:   True   False

  4. A flow specification must state which two numbers?

    • Pump brand and tube colour
    • Room temperature and the date
    • Concentration and residence time

  5. A 6 mL channel is fed at 2 mL each minute. What is the residence time in minutes?

    Answer: ______________

  6. Why does a small reacting volume tame an unstable intermediate?

    • Any burst stays small because almost none is present
    • Small volumes freeze everything solid
    • The intermediate turns stable inside tubes

  7. A student says moving a slow reaction to flow makes it fast. What is wrong?

    • Nothing is wrong: flow speeds every reaction
    • Slow reactions cannot run in flow at all
    • Flow changes control, not the chemistry itself

  8. Which statement about capital cost is fair?

    • Glassware always costs more than flow kit
    • Flow kit costs more upfront than flasks
    • Neither option ever costs anything
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Answer key

For grown-ups. Fold this page away before handing over the rest.

From flask to flow W1-mt_eOjBPoeZSf-s1

  1. Mixing, heat removal, and reacting time · Size shifts all three at once. The chemistry feels a new home.
  2. The fast step that gives off heat · Heat piles up where it is made fastest. That step outruns cooling.
  3. True · The channel holds almost nothing. Little present means little risk.
  4. Concentration and residence time · One number says how strong, the other how long. Both define the run.
  5. 3 · Divide volume by flow rate. The pump sets the wait.
  6. Any burst stays small because almost none is present · Harm scales with amount present. A trace can only make a trace of trouble.
  7. Flow changes control, not the chemistry itself · Control is not speed. The molecules keep their own pace.
  8. Flow kit costs more upfront than flasks · Pumps and channels are bought before the first run. Flasks are cheap.
Worksheet · LightMySky