"Mercury is toxic. Some vaccines used to contain a form of mercury. Therefore, those vaccines were toxic."

Is this a valid logical argument?

Consider the following argument: "If a doctor works too much, they will become stressed. Doctor Smith is stressed. Therefore, Doctor Smith is working too much."

Is this a logically sound conclusion?

All acids are dangerous and corrosive to human skin

Oxygen is the most abundant gas in the Earth's atmosphere

There is no gravity in outer space, which is why astronauts float.

Diamond and graphite are made of entirely different chemical elements.

If the perimeter of Square A is 3 times larger than the perimeter of Square B, how much larger is the area of Square A compared to Square B?

You have 100kg of potatoes that are 99% water. After sitting out, they dry until they are 98% water. What is their new total weight?

Crocodiles can stick out their tongues to catch prey.

The letter 'w' is the only letter in the English alphabet with more than one syllable.

An ostrich's eye is bigger than its brain

In certain conditions, hot water can freeze faster than cold water.

Mercury is the only chemical element on the periodic table that is a liquid at standard room temperature and pressure.