Listening: What is silica gel and is it safe to eat?

Answers and an explanation for each question appear once you add this activity to your own library.

B1 | Listening from video | 12 min

Watch the video (0:06 - 5:17). You can watch more than once, then answer the questions.

How is silica gel different from the sand on a beach?

____ It has a different chemical makeup.____ It is much heavier and much darker.____ It has a porous structure.

A NUMBER from the video.

One gram of silica can have more than ____ square meters of surface area.

ONE WORD from the video.

A normal 5-gram packet can hold about ____ grams of liquid.

Why does a full packet of silica not feel wet?

____ The water is kept inside the tiny tunnels of the beads.____ The beads turn the water into a dry powder.____ The packet lets the water leave through the paper.

Silica gel can only take in water.

____ True____ False____ Not Given

In a place that is only moderately humid, how long can a packet take to fill up?

____ Only a few hours____ Up to a week____ More than a month

Hospitals use silica gel to keep medical tools dry.

____ True____ False____ Not Given

Why do packets say "Do Not Eat"?

____ The silica inside is very poisonous.____ The packet could burn your mouth.____ The packet could block someone's throat.

ONE WORD from the video.

Some silica gel is coated with a toxic compound called ____ chloride.

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