Explanation

 Molecular mass of water (H₂O) = 2(1) + 16 = 18 g/mol

- This means 18 grams of water contains 1 mole of water molecules.  

Explanation

Nitrogen gas (N₂) has a triple covalent bond between the two nitrogen atoms.

This triple bond makes N₂ very stable and unreactive under normal conditions.

Explanation

Gas: No definite shape or volume – Expands to fill any container.

Example: Oxygen, CO₂.

Solid: Fixed shape and volume (e.g., iron).

Liquid: Fixed volume, no fixed shape (e.g., water).

Explanation

Discount means a reduction in the marked or original price of an item.

It is commonly offered during sales, promotions, or special offers to attract buyers.

Explanation

The molar mass of water (H₂O) is 18 grams per mole (H = 1g × 2, O = 16g).

So, 1 mole of water weighs 18 grams.

Explanation

cosecθ − cotθ = (1 - cosθ) / sinθ

Explanation

RBCs lack a nucleus to make more room for hemoglobin, which carries oxygen.

This structure helps them efficiently transport oxygen throughout the body.

Explanation

Use the Gibbs free energy equation:

$$\Delta G=\Delta H-T\Delta S$$

For a process to be spontaneous, $Delta G < 0$

• If $Delta H < 0$ (exothermic)

• And $Delta S > 0$ (entropy increases)

• Then:

  $$\Delta G=\text{negative}-T\times \text{positive}=\text{always negative}$$

 So, no matter the temperature, $Delta G$ will be negative ⇒ spontaneous at all temperatures

Explanation

Ribose and Deoxyribose

Are isomers

• Both are monosaccharides (simple sugars) with the same molecular formula: C₅H₁₀O₅.

• Deoxyribose differs from ribose by one less oxygen atom at the 2' carbon (hence "deoxy").

• They are structural isomers (same formula, different structure).

Explanation

At STP, 1 mole of any gas occupies 22.4 dm³.
If 11.2 dm³ = 0.5 mole →
0.5 mole of nitrogen (N₂) = 14 g
→ Full mole = 28 g (molecular mass of N₂)