Daily Archives: January 15, 2017

Watch a solution change from pink to clear and back again with the hot and cold demonstration. (Ty Nigh) — Valentine’s Day Color Change Chem Demo This is a fun color change chemistry demonstration, just right for Valentine’s Day. Take a pink solution and watch it turn colorless upon heating. When the solution cools it becomes pink again. Here’s what you do: Prepare the Hot and Cold Valentine Solution Add […]

Hot and Cold Pink Color Change Chemistry Demonstration

This entry was posted on January 15, 2017 by Anne Helmenstine (updated on February 1, 2018)

Watch a solution change from pink to clear and back again with the hot and cold demonstration. (Ty Nigh) — Pink Color Change Chem Demo Here’s a fun chemistry demonstration that’s perfect for Valentine’s Day or to illustrate an oxidation-reduction reaction. The Vanishing Valentine involves shaking a solution, causing it to turn pink. If the pink Valentine solution is left undisturbed, it will become colorless. The color change cycle can […]

Vanishing Valentine Chemistry Demonstration

This entry was posted on January 15, 2017 by Anne Helmenstine (updated on February 28, 2020)

Magnesium is used for pencil sharpeners and firestarters. (Firetwister) — Magnesium is the element that is atomic number 12 on the periodic table. It is one of the alkaline earth metals, with a silver appearance in pure form. Here are interesting element facts: Element Atomic Number 12 Facts The symbol for atomic number 12 is Mg. The name magnesium comes […]

Atomic Number 12 Element Facts – Magnesium or Mg

This entry was posted on January 15, 2017 by Anne Helmenstine (updated on January 15, 2017)

Sodium Metal - Atomic Number 11 (Dnn87) — Sodium is the element that is atomic number 11 on the periodic table. It is located in the alkali metals group on the far left side of the periodic table. The pure element is a bright, silver-colored metal at room temperature and pressure. Atomic Number 11 Element Facts Sodium is […]

Atomic Number 11 Element Facts – Na or Sodium

This entry was posted on January 15, 2017 by Anne Helmenstine

The green glow is emitted by phosphorus, atomic number 15, in the presence of oxygen, atomic number 8. Luc Viatour, Creative Commons License — Phosphorus is the element that is atomic number 15 on the periodic table. Phosphorus is an element that is essential for human life and found in many everyday products. Atomic Number 15 Element Facts The symbol for element 15 is P. The element was discovered by alchemist Hennig Brand who was […]

Atomic Number 15 Element Facts

This entry was posted on January 15, 2017 by Anne Helmenstine (updated on April 14, 2020)

Make a hollow penny by dissolving away the zinc to leave copper metal. (United States Mint) — This is an easy chemistry project that uses common materials. You take a post-1982 penny, score the copper surface to expose the zinc interior, react the zinc with acid, and are left with a hollow copper penny. Hollow Penny Materials post-1982 US pennies (metal composition changed in this year) muriatic […]

Hollow Penny Science Project

This entry was posted on January 15, 2017 by Anne Helmenstine (updated on September 6, 2018)