Chemistry In Everyday Life

Step 1: Silicon diode forward drop ≈ 0.7 V.
Step 2: Effective voltage across resistor, VR=20-0.7=19.3 V
Step 3: Current, I=(19.3)/(2000)=9.65 mA

Heavy nuclei have lower binding energy per nucleon. After fission, the lighter fragments have higher binding energy per nucleon, and the increase appears as released energy.

When formaldehyde reacts with ammonia, a well known urinary antiseptic urotropine (also called hexamethylene tetramine) is obtained.

Step 1: Identify the type of dye.
Alizarin is a red dye derived from anthraquinone, making it an anthraquinone dye.
Thus, the correct answer is (4).

Step 1: Identify the use of 2,4-Dichlorophenoxyacetic acid.
2,4-Dichlorophenoxyacetic acid (2,4-D) is commonly used as a herbicide. It is one of the most widely used herbicides for controlling weeds.
Thus, the correct answer is (3).

Step 1: Morphine is a narcotic analgesic and causes addiction.
Step 2: Diazepam is a tranquilizer, not an analgesic.
Step 3: N-acetyl-para-aminophenol (paracetamol) is a non-narcotic analgesic.

Step 1: Talc is chemically hydrated magnesium silicate.
Step 2: Hence magnesium hydrosilicate forms its base.

Step 1: Talc is a naturally occurring mineral.
Step 2: Chemically, talc is hydrated magnesium silicate. Formula: Mg₃Si₄O₁0(OH)₂

Step 1: HCl is a strong acid, so it dissociates completely: .
Step 2: Calculate pH using the formula: Step 3: Verify: For a strong acid, pH depends only on concentration. Matches option (2).