Explanation

• A substance is a piece of matter in pure form, with a specific composition and properties.
• It can be either an element or a compound.

Explanation

Aluminum (Al) is a metal that can easily lose electrons to form ions, making it a reducing agent.

As a reducing agent, aluminum can donate electrons to other substances, causing them to be reduced.

Explanation

• Hydrogen (H2) is the lightest molecule, with a molecular weight of 2.016 g/mol.
• According to Graham's Law of Diffusion, the rate of diffusion of a gas is inversely proportional to the square root of its molecular weight.
• Therefore, hydrogen diffuses the fastest.

Explanation

• De Broglie extended the wave-particle duality to electrons in 1923.
• He proposed that particles such as electrons exhibit wave-like properties.
• A hypothesis that was later confirmed experimentally and became a fundamental concept in quantum mechanics.

Explanation

• Solubility is typically expressed in grams of solute per 100 grams of solvent, denoted as g/100g or g/100mL.
• This unit is called the percentage concentration or percentage composition.

Explanation

• Carbon-12 (C-12) is the most abundant of the two stable isotopes of carbon, amounting to 98.93% of elemental carbon on Earth.
• Carbon-12 is composed of six protons, six neutrons, and six electrons.
• The atomic mass of carbon-12 is exactly 12 Dalton's, by definition.

Explanation

A 10% (w/w) sugar solution means that 10 grams of sugar (the solute) is dissolved in 90 grams of water (the solvent), making a total of 100 grams of solution.

The percentage is calculated as:

(10 g sugar / 100 g total) × 100% = 10% (w/w)

So, 10 grams of sugar is dissolved in 90 grams of water.

Explanation

• Diamond is a crystalline solid that has a sharp melting point.
• Meaning it melts at a specific temperature (around 4000 K) with a minimal range.

Explanation

• Gram atomic mass (GAM) is the atomic mass of an element expressed in grams.
• It represents the mass of one mole of atoms of that element.

Explanation

A diatomic molecule is a molecule composed of two atoms, either of the same element (homogeneous) or different elements (heterogeneous).

Examples of diatomic molecules include:

• Hydrogen (H2)
• Oxygen (O2)
• Nitrogen (N2)