Explanation
Aluminum and Chromium both have similar oxidation states (+3) and chemical properties. Al³⁺ can substitute Cr³⁺ in Cr₂O₃ due to comparable ionic radii and charge. Show/Hide Explanation
کم سے کم مستحکم کاربنین _____ ہے؟
Explanation
The tertiary carbanion (CH₃)₃C⁻ is the least stable because the negative charge is not effectively stabilized by resonance or inductive effects. Tertiary carbanions are highly unstable compared to secondary and primary carbanions. Show/Hide Explanation
Explanation
To boil 1 liter of water from 15°C to 100°C, the energy required is:
Q = mcΔT
= 1 kg × 4.18 kJ/kg°C × (100°C - 15°C)
= 1 × 4.18 × 85
= 355 kJ
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بڑھتی ہوئی تعدد کے سلسلے میں ورنکرم علاقوں کا صحیح حکم _____ ہے؟
Explanation
RF (Radio frequency) has the lowest frequency, followed by IR (Infrared), ViS (Visible spectrum), and then UV (Ultraviolet), which has the highest frequency. This order follows the sequence of increasing frequency in the electromagnetic spectrum. Show/Hide Explanation
Explanation
H₂S in dilute HCl is used to separate metal ions based on their solubility as sulfides. Bi³⁺ and Sn⁴⁺ do not separate easily. Because they both form insoluble sulfides under similar conditions. Show/Hide Explanation
Explanation
For a strong acid with a high K a K_a K a , it fully ionizes in water. pH is calculated as p H = − log [ H + ] pH = -log[H^+] [ H + ] = 10 − 4 [H^+] = 10^{-4} pH = 4.
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برقی مقناطیسی لہروں کی رفتار ______ ہے؟
Explanation
The velocity of electromagnetic waves (EM waves) in a vacuum is approximately 3 × 10⁸ meters per second. This speed is constant for all EM waves, including light, radio waves, and X-rays, in a vacuum. Show/Hide Explanation
Explanation
On the moon, there is no atmospheric pressure , which lowers the boiling point of water. Since the water is at 300°C, it will immediately boil once the lid is opened. Show/Hide Explanation
دھاتوں کی غیر مساوی توسیع آپریشن کو ____ ممکن بناتی ہے؟
Explanation
Thermostats work based on the unequal expansion of metals in a bimetallic strip. This property helps in regulating temperature by switching devices on or off. Show/Hide Explanation
خشک سیل میں الیکٹرولائٹ ______ کا نم پیسٹ ہے؟
Explanation
In a dry cell, the electrolyte is a moist paste of ammonium chloride (NH₄Cl) and zinc chloride (ZnCl₂) to facilitate ion flow. It helps in the movement of electrons between the zinc anode and the manganese dioxide cathode. Show/Hide Explanation
