DCOA Mixed Practice Test #53

Question 1

Kumaranasan 3 major works:‌​‍

Accepted Answer

Veenapoovu, Chandala Bhikshuki, Chintavishtayaya Sita — Several landmark poems.‌​‍

Answer

Many

Answer

Two

Answer

Only one

Question 2

Liquid metal at room temp:‌​‍

Accepted Answer

Mercury — Mercury (Hg).‌​‍

Answer

Gold

Answer

Silver

Answer

Tin

Question 3

Vitamin K is for:‌​‍

Accepted Answer

Blood clotting — Blood clotting. Source: green leafy vegetables.‌​‍

Answer

Vision

Answer

Energy

Answer

Bone strength

Question 4

DNA fingerprinting probes target:‌​‍

Accepted Answer

VNTRs (Variable Number Tandem Repeats) — highly polymorphic — Unique pattern per individual (except identical twins). ‌​‍Forensics, paternity, wildlife. Minisatellites and microsatellites.

Answer

Coding DNA

Answer

Centromeres

Answer

Only exons

Question 5

Acetone is used as a:‌​‍

Accepted Answer

Solvent (e.g., nail polish remover) — Acetone (propan-2-one) is a widely used solvent due to its polarity and volatility.‌​‍

Answer

Fuel

Answer

Acid

Answer

Fertiliser

Question 6

Longyearbyen, the northernmost human settlement, is in:‌​‍

Accepted Answer

Svalbard Islands (Norway) — Longyearbyen is on Spitsbergen island of the Svalbard archipelago, Norway.‌​‍

Answer

Alaska

Answer

Greenland

Answer

Siberia

Question 7

Charles's law states (at constant pressure):‌​‍

Accepted Answer

V/T = constant — Charles's law: V ∝ T (absolute) at constant P.‌​‍

Answer

V × T = constant

Answer

PV = constant

Answer

P/V = constant

Question 8

Mr. Suresh observes that his students often become noisy and disorganised during the transition from one activity (e.g., math to science) to another. What is the most effective strategy Mr. Suresh can implement to improve these transitions?

Accepted Answer

B. Provide clear, concise instructions and practice transition routines regularly. — Clear, concise instructions and regular practice of transition routines help students move smoothly and efficiently between activities, reducing noise and disorganization. Allowing free talk can exacerbate chaos, and using a bell or punishment alone does not teach students the expected procedures for transitions.

Answer

A. Allow students to talk freely during transitions to release energy.

Answer

C. Use a loud bell to signal the start and end of every transition period.

Answer

D. Punish students who take too long to transition by making them stay after class.

Question 9

Symbol of Silver:‌​‍

Accepted Answer

Ag — Ag (Argentum).‌​‍

Answer

Si

Answer

Au

Answer

Sv

Question 10

Lucas test distinguishes alcohols by:‌​‍

Accepted Answer

Rate of cloudiness with Lucas reagent (conc. HCl + ZnCl₂): 3°<1 min, 2° ~5 min, 1° no rxn at RT — Tests 1°, 2°, 3° alcohols by cloudiness of alkyl chloride formed.‌​‍

Answer

Colour

Answer

Smell

Answer

Boiling point

DCOA Mixed Practice Test #53