Periodic Table - First 20 Elements

Explanation
The letter 'H' stands for hydrogen. Hydrogen is a chemical element with the symbol H and atomic number 1. It is the lightest and most abundant element in the universe, making up about 75% of its elemental mass. Hydrogen is a colorless, odorless, and highly flammable gas. It is commonly used in various industries, such as fuel cells, rocket propellants, and as a reducing agent in chemical reactions.

Explanation
The symbol for Helium is He.

Explanation
The correct answer is "Beryllium, beryllium." Beryllium is a chemical element with the symbol Be and atomic number 4. It is a lightweight metal that is commonly used in various industries due to its high strength, low density, and excellent thermal and electrical conductivity. The repetition of "beryllium" in the answer emphasizes the correct spelling and capitalization of the word.

Explanation
The given correct answer is B. This suggests that the question is asking for the chemical symbol for the element Boron, which is B.

Explanation
The symbol for carbon on the periodic table is C.

Explanation
The correct answer is "N" because "nitrogen" is the full name of the element, and its chemical symbol is "N". The symbol "N" is derived from the first letter of the element's name, making it the correct answer.

Explanation
The correct answer is F, which stands for fluorine. Fluorine is a chemical element with the symbol F and atomic number 9. It is a highly reactive and corrosive pale yellow gas. Fluorine is the lightest halogen and is found in compounds such as fluorides. It is widely used in industries for various purposes, including the production of fluorocarbons and fluoropolymers. Fluorine also has several applications in dental health as it is used in fluoride treatments and toothpaste to prevent tooth decay.

Explanation
Fluorine is the correct answer because it is the chemical element represented by the symbol F. It is a highly reactive and corrosive gas that belongs to the halogen group on the periodic table. Fluorine is known for its strong oxidizing properties and is commonly used in various industries such as pharmaceuticals, electronics, and manufacturing.

Explanation
The correct answer is Na, which is the chemical symbol for sodium.

Explanation
The correct answer is Mg because Mg is the chemical symbol for magnesium.

Explanation
Silicon is a chemical element with the symbol Si. The symbol "Si" represents the atomic symbol for silicon. Silicon is a commonly used element in various industries due to its unique properties, such as its ability to conduct electricity and its abundance in the Earth's crust. It is widely used in the production of semiconductors, solar cells, and other electronic devices. Therefore, "Si" is the correct answer to represent silicon.

Explanation
The correct answer is Ca, which is the chemical symbol for calcium. Calcium is a chemical element with the atomic number 20. It is an essential mineral for the human body, playing a crucial role in bone health, muscle contraction, nerve function, and blood clotting. The symbol "Ca" is derived from the Latin word "calcis," meaning lime or limestone, which is a common source of calcium.