Explanation

A typical diffraction grating can have 400 to 50,000 lines per centimeter, depending on precision and application.

Higher line densities provide better spectral resolution for analyzing light.

Explanation

Manganese (Mn) shows a maximum oxidation state of +7, as seen in compounds like KMnO₄ (potassium permanganate).

This is higher than the maximum oxidation states of Cr (+6), P (+5), and S (+6).

Explanation

Icily means گرم جوشی یا جذبات کی کمی

Coldly means سخت ، غیر دوستانہ ، یا غیر جذباتی انداز میں بات کرنا

Explanation

Iso-octane (2,2,4-trimethylpentane) is assigned an octane number of 100 because it resists knocking in engines.

It serves as the standard reference fuel for high-quality performance in internal combustion engines.

Explanation

Glycine is the simplest and neutral amino acid, with no extra acidic or basic side chains.

It has a hydrogen atom as its side group (R group), making it electrically neutral at physiological pH.

Explanation

In methane (CH₄), the carbon atom forms four sigma bonds with hydrogen atoms.

To form these four equivalent bonds, carbon undergoes sp³ hybridization, resulting in a tetrahedral structure.

Explanation

Chlorofluorocarbons (CFCs) release chlorine atoms in the stratosphere, which break down ozone (O₃) molecules.

This reaction is the main cause of ozone layer depletion.

Explanation

The coordination number of a metal atom in a complex is the number of ligands directly attached to it.

In [PtCl(NO)(NH₃)₂], the ligands are:

• Cl⁻ (1)
• NO (1)
• NH₃ (2)

Total number of ligands = 1 + 1 + 2 = 4

The coordination number of Pt is 4, since it is bonded to 4 ligands.

Explanation

The phrase "When I met him" is in the past tense, so we need a past continuous verb to show an action in progress at that time.

"Was going" correctly shows he was in the process of going to college when the meeting happened.

Explanation

Elements of Group IVA (Group 14) like carbon (C) and silicon (Si) have very high melting points due to strong covalent bonding.

For example, diamond (carbon) has the highest melting point among all elements.