C++ | MCQs

Explanation

"6.022 × 10²³ atoms of carbon"

Correct — Each CO₂ molecule contains 1 carbon atom

So, 1 mole of CO₂ has 6.022 × 10²³ carbon atoms

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

 The precise definition of organic chemistry is the Study of carbon-containing compounds. 

Organic chemistry focuses on the study of compounds that contain carbon, regardless of whether they are hydrocarbons or their derivatives.

While hydrocarbons are a subset of organic compounds, the definition encompasses all carbon-based molecules

Explanation

Alkaline earth metals: These elements have two valence electrons in their outermost s orbital.

3rd period: In the third period, the outermost shell is the 3rd shell. 

Therefore, the electronic configuration of an alkaline earth metal in the 3rd period is [Ne] 3s².

Explanation

 The enthalpy change during the formation of one mole of a compound from its elements in their standard states is called standard heat of formation. 

Explanation

In an atom, no two electrons can have the same set of four quantum numbers.

This is known as the Pauli Exclusion Principle.

The four quantum numbers are: 

Explanation

 The charge of cathode ray particles can be determined by passing them through oppositely charged plates. 

Cathode rays are composed of negatively charged particles called electrons.

When these rays pass through an electric field with oppositely charged plates

They are deflected towards the positively charged plate, demonstrating their negative charge. 

Explanation

Each molecule of water (H₂O) has 10 electrons (2 from hydrogen and 8 from oxygen).

Therefore, 1 mole of water has 10 moles of electrons.

So, 10 moles of water have 10 x 10 = 100 moles of electrons.

Explanation

 In cyclic photophosphorylation, electrons from the primary acceptor of Photosystem I (PSI) return to the cytochrome complex, specifically the cytochrome b6f complex, via ferredoxin (Fd)

.This process also involves plastoquinone (PQ) and plastocyanin (Pc) before the electrons return to PSI. 

Explanation

Anthracite is the hardest and most mature form of coal, containing the highest percentage of carbon (about 86–98%).

It burns cleanly with very little smoke.

It has the highest energy content among coal types.