General Science/Everyday Science MCQs
Topic Notes: General Science/Everyday Science
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
61
The 'valence' of an atom refers to:
Answer:
The number of electrons in the outermost shell
Valence electrons are the electrons in the outermost shell of an atom. They determine the chemical reactivity and bonding capacity of the element.
62
Which of these diseases is characterized by the swelling of the parotid (salivary) glands?
Answer:
Mumps
Mumps is a viral infection that primarily affects the salivary glands located near the ears. This results in the characteristic 'puffy cheeks' and swollen jaw that are the hallmark symptoms of the disease.
63
The term 'MRSA' stands for Methicillin-resistant Staphylococcus aureus. What does this indicate about the bacteria?
Answer:
It is a strain of bacteria that has become resistant to many common antibiotics
MRSA is a 'superbug' that has evolved resistance to methicillin and other related antibiotics (like penicillin and oxacillin). It is a significant concern in healthcare settings because it causes infections that are very difficult to treat with standard medical protocols.
64
Which of the following is the most reactive halogen?
Answer:
Fluorine
Fluorine is the most reactive halogen because of its small size and very high electronegativity, which allows it to attract and gain electrons more vigorously than any other element.
65
In which block of the Periodic Table is Hydrogen placed?
Answer:
s-block
Hydrogen has the configuration $1s^1$, placing it in the s-block. However, because it shares properties with both Group 1 (one valence electron) and Group 17 (needs one electron to fill shell), its position is often debated.
66
According to the Kinetic Molecular Theory, the temperature of a gas is directly proportional to what?
Answer:
The average kinetic energy of the particles
Temperature is a measure of the average kinetic energy of the particles in a substance. As the temperature of a gas increases, the particles move faster, resulting in a higher average kinetic energy.
67
Which block elements are generally known as the 'Inner Transition Elements'?
Answer:
f-block
The f-block elements (Lanthanides and Actinides) are called inner transition elements because they are 'within' the transition metals of the d-block and involve the filling of the $(n-2)f$ subshells.
68
The elements that have the properties of both metals and non-metals are called:
Answer:
Metalloids
Metalloids lie along the 'staircase' line in the p-block and show a mix of metallic and non-metallic properties, often acting as semiconductors.
69
What is the main reason for 'food poisoning' after eating old or improperly stored food?
Answer:
Toxic substances produced by bacteria like Salmonella or Staphylococcus
Food poisoning is often caused by eating food contaminated with bacteria or the toxins they produce while growing on the food. Salmonella and Staphylococcus aureus are common culprits that cause vomiting and diarrhea shortly after ingestion.
70
Which of the following is a characteristic of noble gases?
Answer:
Full outer electron shells
Noble gases (Group 18) are very stable and unreactive because they have a complete valence shell (octet), meaning they have no tendency to gain or lose electrons.