All Free Everyday Science MCQs with Answers

291. The distance of mercury from sun is__________?

• A. 56 million km
• B. 57.9 million km
• C. 58.9 million km
• D. 59.1 million

Explanation: Mercury's mean distance from the Sun is about 57.9 million kilometres, although its elliptical orbit causes this distance to vary. The other figures are only rough alternatives and are less accurate.

292. Moon light reaches to earth in___________seconds?

• A. 0.3 seconds
• B. 1.3 seconds
• C. 2.3 seconds
• D. 3.3 seconds

Explanation: Moonlight is reflected sunlight, so it takes approximately the same time as sunlight to travel from the Moon to Earth, about 1.3 seconds. The Moon is roughly 384,000 km away.

293. Which planet is much brighter in our solar system?

• A. Earth
• B. Venus
• C. Mercury
• D. Jupiter

Explanation: Venus is the brightest planet as seen from Earth because it is relatively close and has highly reflective clouds. Jupiter can also appear bright, but it is generally fainter than Venus.

294. Evaporation is _________ ?

• A. Cooling process
• B. Exothermic process
• C. Bottom process
• D. Rare processEveryday Science MCQs

Explanation: Evaporation causes cooling because the fastest, highest-energy molecules escape from the liquid surface, leaving lower-energy molecules behind. It is therefore an endothermic cooling process, not an exothermic one.

295. Which gas is most commonly used in neon signs?

• A. Argon
• B. Neon
• C. Krypton
• D. Xenon

Explanation: Neon signs traditionally use low-pressure neon gas, which glows reddish-orange when electrically excited. Other noble gases can produce different colours in discharge tubes, but they are not the defining gas of neon signs.

296. Nucleus of an atom was discovered by___________?

• A. Goldstein
• B. James Chadwick
• C. J J Thomson
• D. Rutherford

Explanation: Rutherford’s gold-foil experiment showed that nearly all the atom’s positive charge and mass are concentrated in a tiny central nucleus. Thomson discovered the electron, while Chadwick discovered the neutron.

297. The molecular mass of Water molecule is __________?

• A. 16amu
• B. 17amu
• C. 18amu
• D. 20amu

Explanation: A water molecule contains two hydrogen atoms and one oxygen atom, so its molecular mass is 2(1) + 16 = 18 atomic mass units. This is written as H₂O.

298. Vertical columns in the periodic table of elements are called as__________?

• A. Periods
• B. Groups
• C. Rows
• D. Lanthanoids series

Explanation: The vertical columns of the periodic table are called groups, and elements in a group generally have similar valence-electron arrangements and chemical properties. Horizontal rows are called periods.

299. Element extracted from Sea water?

• A. Beryllium
• B. Magnesium
• C. Aluminium
• D. None of These

Explanation: Magnesium compounds are present in seawater and magnesium metal is commercially obtained from them, commonly by electrolysis of molten magnesium chloride. Beryllium and aluminium are not normally extracted from seawater on this basis.

300. The property by virtue of which metals can be beaten into thin sheets is known as?

• A. Ductility
• B. Malleability
• C. Conductivity
• D. Density

Explanation: Malleability is the ability of a metal to be hammered or pressed into thin sheets. Ductility is the related ability to be drawn into wires.