KPPSC Test Everyday Science Syllabus

What is the difference between atomic number and mass number?

Atomic number is the number of protons in an atom; mass number is the total number of protons and neutrons in the nucleus.

What are isotopes?

Atoms of the same element having the same number of protons (same atomic number) but different numbers of neutrons (different mass numbers), e.g. Carbon-12 and Carbon-14.

Who arranged the modern periodic table and on what basis are elements arranged?

The modern periodic table is based on Moseley's work arranging elements by increasing atomic number; Mendeleev created the earlier table based on atomic mass.

What are the horizontal rows and vertical columns of the periodic table called?

Horizontal rows are called periods; vertical columns are called groups.

Name the most reactive group of metals and the most reactive group of non-metals in the periodic table.

Alkali metals (Group 1) are the most reactive metals; halogens (Group 17) are the most reactive non-metals.

What is the pH scale range, and what do values below 7, equal to 7, and above 7 indicate?

pH ranges from 0 to 14; below 7 is acidic, exactly 7 is neutral, above 7 is basic (alkaline).

What ions do acids and bases produce in water?

Acids release hydrogen ions (H⁺); bases (alkalis) release hydroxide ions (OH⁻) in aqueous solution.

What is a salt, and give the general reaction that forms it.

A salt is an ionic compound formed when an acid reacts with a base. Acid + Base → Salt + Water (neutralisation).

What colour does litmus paper turn in acids and in bases?

Blue litmus turns red in acids; red litmus turns blue in bases (acids redden, bases blue).

Give the chemical names for the common compounds: common salt, baking soda, and washing soda.

Common salt = sodium chloride (NaCl); baking soda = sodium bicarbonate (NaHCO₃); washing soda = sodium carbonate (Na₂CO₃·10H₂O).

What are the chemical formulas of water, carbon dioxide and ammonia?

Water = H₂O; carbon dioxide = CO₂; ammonia = NH₃.

What gas is known as laughing gas, and what is quicklime chemically?

Laughing gas is nitrous oxide (N₂O); quicklime is calcium oxide (CaO).

What is the basic structural and functional unit of life?

The cell.

What is the difference between a prokaryotic and a eukaryotic cell?

Prokaryotic cells lack a true (membrane-bound) nucleus and membrane-bound organelles (e.g. bacteria); eukaryotic cells have a true nucleus and membrane-bound organelles (e.g. plant and animal cells).

What is a gene, and where are genes located?

A gene is a segment of DNA that carries the code for a specific trait; genes are located on chromosomes within the cell nucleus.

How many chromosomes are in a normal human body cell, and which pair determines sex?

46 chromosomes (23 pairs); the 23rd pair (sex chromosomes) determines sex — XX in females, XY in males.

Which organelle is the 'powerhouse of the cell' and why?

The mitochondrion; it produces energy (ATP) through cellular respiration.

What is the function of red blood cells and which protein in them carries oxygen?

Red blood cells transport oxygen (and some carbon dioxide); the oxygen-carrying protein is haemoglobin.

Name the largest organ of the human body and the largest internal organ.

The skin is the largest organ overall; the liver is the largest internal organ.

Which organ system is responsible for producing insulin, and which organ produces it?

The endocrine system; insulin is produced by the pancreas (by the beta cells of the islets of Langerhans).

What are the functional units of the kidney called?

Nephrons.

Which vitamin deficiency causes scurvy, and which causes rickets?

Vitamin C deficiency causes scurvy; Vitamin D deficiency causes rickets.

Which vitamin is needed for good vision, and its deficiency causes night blindness?

Vitamin A; its deficiency causes night blindness.

Which vitamins are fat-soluble and which are water-soluble?

Fat-soluble vitamins are A, D, E and K; water-soluble vitamins are the B-complex group and Vitamin C.

What is the difference between a deficiency disease and an infectious disease?

A deficiency disease results from lack of a nutrient (e.g. scurvy, rickets) and is non-communicable; an infectious disease is caused by pathogens (bacteria, viruses, etc.) and can spread between people.

What type of pathogen causes malaria, and which organism transmits it?

Malaria is caused by the Plasmodium parasite (a protozoan), transmitted by the bite of the female Anopheles mosquito.

What is immunity, and what is the difference between active and passive immunity?

Immunity is the body's ability to resist infection. Active immunity is produced by the body's own antibodies (e.g. after infection or vaccination); passive immunity is acquired by receiving ready-made antibodies (e.g. from mother or antiserum).

Name the planets of the solar system in order from the Sun.

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

Which is the largest planet, the smallest planet, and the hottest planet in the solar system?

Largest planet: Jupiter; smallest planet: Mercury; hottest planet: Venus (due to its thick CO₂ atmosphere).

What galaxy is the solar system part of, and what shape is it?

The Milky Way galaxy, which is a spiral galaxy.

List the layers of the Earth from outside to centre.

Crust, mantle, outer core (liquid), and inner core (solid).

Name the main layers of Earth's atmosphere from the surface upward.

Troposphere, stratosphere, mesosphere, thermosphere, and exosphere.

In which atmospheric layer is the ozone layer found, and what does it do?

The ozone layer is in the stratosphere; it absorbs most of the Sun's harmful ultraviolet (UV) radiation.

What is the difference between a solar eclipse and a lunar eclipse?

A solar eclipse occurs when the Moon passes between the Sun and Earth (new moon), blocking the Sun; a lunar eclipse occurs when the Earth passes between the Sun and Moon (full moon), casting its shadow on the Moon.

During which lunar phase does a solar eclipse occur, and during which does a lunar eclipse occur?

A solar eclipse occurs at new moon; a lunar eclipse occurs at full moon.

What causes day and night on Earth?

The rotation of the Earth on its axis (one rotation ≈ 24 hours); the side facing the Sun has day, the side facing away has night.

What causes the seasons on Earth?

The tilt of the Earth's axis (about 23.5°) combined with its revolution around the Sun, which changes the angle and duration of sunlight received by each hemisphere.

How long does the Earth take to rotate on its axis and to revolve around the Sun?

It takes about 24 hours to rotate once on its axis and about 365.25 days to complete one revolution around the Sun.

What do the abbreviations CPU, RAM and ROM stand for?

CPU = Central Processing Unit; RAM = Random Access Memory; ROM = Read Only Memory.

What is the difference between hardware and software?

Hardware is the physical components of a computer (e.g. monitor, keyboard, CPU); software is the set of programs and instructions that run on the hardware (e.g. operating system, applications).

Order these data units from smallest to largest: gigabyte, bit, byte, kilobyte, megabyte.

Bit, byte, kilobyte, megabyte, gigabyte (8 bits = 1 byte; 1024 bytes = 1 KB; 1024 KB = 1 MB; 1024 MB = 1 GB).

What number system does a computer use internally, and what are its two digits?

The binary number system; its two digits are 0 and 1.

What do the abbreviations WWW, HTTP and URL stand for?

WWW = World Wide Web; HTTP = HyperText Transfer Protocol; URL = Uniform Resource Locator.

What is an artificial satellite, and name a common use of communication satellites.

An artificial satellite is a human-made object placed in orbit around Earth; communication satellites relay TV, telephone, internet and radio signals over long distances.

What is a geostationary satellite?

A satellite in an orbit about 36,000 km above the equator with a period of 24 hours, so it appears to stay fixed over one point on Earth; used for communication and weather monitoring.

What is GPS and what is it used for?

GPS (Global Positioning System) is a satellite-based navigation system that uses a network of satellites to determine precise location, time and velocity anywhere on Earth.