77 (number) facts for kids

77 is a special natural number that comes right after 76 and just before 78. A natural number is simply a counting number, like 1, 2, 3, and so on. What makes 77 interesting is that it's a palindromic number. This means it reads the same forwards and backwards! Think of words like "madam" or "racecar" – 77 works the same way with numbers.

What Makes 77 Special?

The number 77 has some cool facts connected to it, especially in the world of science. It's not just a number you use for counting; it shows up in different places.

77 in Science

In science, the number 77 is important for a few reasons:

• Iridium: 77 is the atomic number of a metal called iridium. The atomic number tells us how many protons are in an atom's nucleus. Iridium is a very hard, shiny, and rare metal. It's often used in things that need to be super strong and resistant to heat, like spark plugs or special electrical contacts.
• Nitrogen's Boiling Point: The number 77 also represents the boiling point of nitrogen when measured in kelvins. Kelvin is a special scale used to measure temperature, especially in science. Nitrogen is a gas that makes up most of the air we breathe. It boils, or turns from a liquid into a gas, at a very cold temperature of 77 kelvins. This is equal to about -196 degrees Celsius or -321 degrees Fahrenheit!

See Also

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• In Spanish: Setenta y siete para niños