➤ Gamma rays have wavelengths less than ($< 10^{-3} \, \text{nm}$ and are produced in nuclear reactions and radioactive decay.
★ Gamma radiation is the most energetic form of electromagnetic radiation.

➤ Passing electricity through water breaks it down into hydrogen and oxygen, a classic example of decomposition reaction.
★ Electrolysis of water is a chemical decomposition process using electricity.

➤ In the reaction, nitrogen (N) is oxidized and oxygen (O) is reduced.
★ This is a redox reaction where ammonia is oxidized and oxygen acts as the oxidizing agent.

➤ Argon is an inert gas used in welding to shield the metal from atmospheric gases that may cause defects.
★ Argon is preferred in TIG (Tungsten Inert Gas) welding due to its non-reactive nature.

➤ In Newlands’ Octaves, every 8th element had similar properties; lithium and sodium share similar chemical properties.
★ Sodium was the 8th element after lithium in the early periodic table arrangement.

➤ Fats and oils undergo oxidation, not reduction, causing them to turn rancid.
★ Antioxidants and nitrogen flushing help prevent oxidation and spoilage.

➤ Rutherford used a 1000-atom-thick gold foil to study alpha particle deflection and discover the atomic nucleus.
★ The gold foil experiment led to the discovery of the positively charged nucleus.

➤ Alkaline earth metals are found in Group 2A, and include elements like calcium, strontium, and radium.
★ These elements form basic oxides and have two valence electrons.

➤ Fullerene was discovered in 1985 by Robert F Curl, Harold W Kroto, and Richard E Smalley, who were awarded the Nobel Prize for the discovery.
★ Fullerene consists of carbon atoms arranged in a spherical structure, commonly known as buckminsterfullerene ($\text{C}_{60}$).

➤ The milkman adds baking soda to increase the pH of milk slightly, making it slightly alkaline, which helps prevent souring and extends shelf life.
★ A higher pH helps prevent bacterial growth that causes milk to spoil.

➤ Silver chloride decomposes under light exposure to form silver and chlorine gas, causing it to turn grey.
★ This is a photochemical reaction where light acts as the catalyst for the decomposition.

➤ Grignard reagents are organomagnesium compounds, and the correct representation is $\text{CH}_3\text{-Mg-Cl}$.
★ Grignard reagents are highly reactive and are used in organic synthesis to form carbon-carbon bonds.

➤ Formic acid $\text{HCOOH}$ is the most acidic due to the absence of any alkyl group, making it a stronger acid compared to others.
★ The presence of alkyl groups in other acids makes them less acidic because they donate electrons, reducing the acidic strength.

➤ The oxidation state of sulfur (S) in $\text{H}_2\text{S}_2\text{O}_7$ is $+6$.
★ The sum of oxidation numbers in a molecule must equal zero; sulfur’s oxidation number is calculated based on the oxidation state of oxygen (-2) and hydrogen (+1).

➤ The weight percentage of carbon in glucose is calculated as:
$\frac{6 \times 12}{6 \times 12 + 12 \times 1 + 6 \times 16} \times 100 \approx 40\%$
★ Glucose contains 40% carbon by mass

➤ Plasma is a state of matter consisting of charged particles. Neon sign bulbs are an example of plasma, where neon gas is ionized.
★ Plasma is the fourth state of matter, distinct from solids, liquids, and gases.

➤ The brown fumes emitted when lead nitrate is heated are nitrogen dioxide ($\text{NO}_2$), a reddish-brown gas formed due to the decomposition of lead nitrate.
★ Nitrogen dioxide is a toxic gas formed in the process of heating certain nitrogen compounds like lead nitrate.

➤ The rate constant doubles for most reactions when the temperature increases by 10°C, as per the Arrhenius equation.
★ A 10°C rise in temperature typically results in a doubling of the rate constant for many reactions.

➤ Neon gas emits red light when electricity is passed through it, which is why neon signs typically glow red.
★ Neon is commonly used in neon lighting due to its distinctive red glow under electric discharge.

➤ Mendeleev predicted the atomic mass of eka-aluminium to be 68, which was later confirmed as the atomic mass of gallium.
★ Mendeleev’s predictions about undiscovered elements were largely accurate, and the discovery of gallium validated his periodic law.

➤ Mendeleev predicted ekasilicon, and later germanium was discovered with properties closely matching his predictions.
★ This successful prediction supported the validity of Mendeleev’s periodic table

➤ Fisher’s equation $\text{MV} = \text{PT}$ relates money supply (M), velocity (V), price level (P), and transactions (T).
★ It represents the quantity theory of money in classical economics.

➤ Amedeo Avogadro proposed that equal volumes of gases at the same temperature and pressure contain the same number of molecules, reconciling Dalton’s atomic theory with Gay-Lussac’s observations.
★ Avogadro’s hypothesis was fundamental in the development of the concept of the mole.

➤ Lavoisier’s Law of Conservation of Mass states that mass is neither created nor destroyed in a chemical reaction, laying the foundation for modern chemistry.
★ Lavoisier’s work is considered the beginning of the scientific study of chemistry.

➤ Willebrord Snellius first stated the principle of refraction and introduced the concept of the refractive index, which defines how much light bends when passing through different substances.
★ The Snell’s Law is fundamental in optics and explains the relationship between the angle of incidence and the angle of refraction.