220-1101 Mobile Devices Practice Question

A user accidentally spills coffee over their smartphone. They immediately pick it up and wipe the exterior. The phone is still powered on and functioning, but the touchscreen is not responding correctly in the area where the liquid was spilled. Which of the following should the user do FIRST to prevent further damage?

⚠ Common exam trap

CompTIA often tests the misconception that rice or heat are effective drying methods, when in fact the priority is to cut power to prevent electrochemical damage, not to dry the device first.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Power off the phone and remove the battery if possible.

Powering off the phone and removing the battery (if possible) immediately stops electrical current from flowing through the device, which prevents short circuits and electrochemical corrosion caused by the conductive and corrosive nature of coffee. This is the first and most critical step to mitigate damage to the motherboard and other internal components.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
Place the phone in a bag of uncooked rice for 24 hours.
Why it's wrong here
Uncooked rice is a poor desiccant for electronics; it lacks the ability to draw moisture from sealed internals, and the starch dust it sheds can contaminate ports and connectors. Leaving the phone in rice for 24 hours only delays proper disassembly and drying, allowing water to corrode metal traces and bridge circuits. Silica gel packets or a professional drying service are far more effective, but never as a substitute for powering off and disassembling the device.
✓
Power off the phone and remove the battery if possible.
Why this is correct
Immediately powering off the phone cuts all electrical current through the wet circuitry, which is the primary driver of electrolysis, corrosion, and short-circuit damage. If the battery is removable, extracting it eliminates any residual power source and prevents voltage from reaching liquid-contaminated components. For sealed phones, holding the power button to shut down and avoiding any charging or button presses until thoroughly dry is still the critical first line of defense.
✗
Use a hairdryer on high heat to dry the phone.
Why it's wrong here
A hairdryer's high heat can exceed the thermal limits of internal components, warping plastic connectors and weakening the adhesive that holds the screen and chassis together. The forced airflow can also push liquid deeper into the logic board assembly, beneath chips, and into display layers, making the damage worse than a simple soak. Even on a cool setting, the risk of driving water further into crevices remains, so the proper approach is to pat dry external surfaces and allow the device to air dry in a well-ventilated area.
✗
Continue using the phone and hope it dries out naturally.
Why it's wrong here
Continuing to use a wet phone keeps electrical current flowing through conductive water, which instantly risks short-circuiting the battery, power management IC, and motherboard. Even if the phone appears to function, moisture trapped under components will continue to oxidize solder joints and trace pads, often causing intermittent failures or complete failure days later. The phone also generates heat during operation, accelerating chemical reactions that degrade internal contacts and shorten the device's lifespan.

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220-1101 Mobile Devices Practice Question

Why each option matters

Option-by-option breakdown

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