Which of the following are scientific facts?

Question

Species evolve through the process of natural selection.

Water boils at
.

Tin expands as it is heated.

Many diseases are caused primarily by microorganisms too small to be seen with the naked eye.

All objects in the universe are attracted to one another through the force of gravity.

The air we breath on Earth is mostly nitrogen.

Answer 1

The statements you provided can generally be considered scientific facts based on current scientific understanding. Here's an evaluation of each:

1. Species evolve through the process of natural selection.

   • This is a core principle of evolutionary biology and is widely supported by evidence.

2. Water boils at [insert temperature].

   • This is context-dependent. Water boils at 100 degrees Celsius (212 degrees Fahrenheit) at standard atmospheric pressure, but this can vary with changes in pressure.

3. Tin expands as it is heated.

   • This statement is true and can be measured; it reflects the general behavior of materials when they are heated.

4. Many diseases are caused primarily by microorganisms too small to be seen with the naked eye.

   • This statement is accurate; numerous diseases are caused by bacteria, viruses, fungi, and protozoa.

5. All objects in the universe are attracted to one another through the force of gravity.

   • This is a fundamental principle of physics as described by Newton's law of universal gravitation and later by Einstein's theory of general relativity.

6. The air we breathe on Earth is mostly nitrogen.

   • This is correct; approximately 78% of Earth's atmosphere is nitrogen, making it the most abundant gas.

In summary, all of these statements can be considered scientific facts, although the boiling point of water is conditional upon atmospheric pressure.