List-I (Sol) | List-II (Method of preparation) |
---|---|
A) \( \text{As}_2\text{S}_3 \) | I) Bredig's arc method |
B) \( \text{Au} \) | II) Oxidation |
C) \( \text{S} \) | III) Hydrolysis |
D) \( \text{Fe(OH)}_3 \) | IV) Double decomposition |
Let \( A = \{-3, -2, -1, 0, 1, 2, 3\} \). A relation \( R \) is defined such that \( xRy \) if \( y = \max(x, 1) \). The number of elements required to make it reflexive is \( l \), the number of elements required to make it symmetric is \( m \), and the number of elements in the relation \( R \) is \( n \). Then the value of \( l + m + n \) is equal to:
For hydrogen-like species, which of the following graphs provides the most appropriate representation of \( E \) vs \( Z \) plot for a constant \( n \)?
[E : Energy of the stationary state, Z : atomic number, n = principal quantum number]
The number of 6-letter words, with or without meaning, that can be formed using the letters of the word MATHS such that any letter that appears in the word must appear at least twice, is $ 4 \_\_\_\_\_$.
The study of the chemical phenomena that occur at the interface of two surfaces which can be solid-liquid, solid-gas, solid-vacuum, liquid-gas, etc.
Read Also: Surface Chemistry
Applications of surface chemistry are:
The process of attraction and aggregation of the molecules of a substance on the surface of a solid is known as adsorption. For Example, N2 adsorbs on the surface of activated charcoal
Two types of adsorption are:-
The process through which the refined metals convert themselves into more stable compounds is known as corrosion.
The type of technique used in order to purify the substances to separate Solids from liquids is known as crystallisation.
The process wherein a catalyst is used in order to increase the rate of a chemical reaction is known as catalysis. The catalyst does not undergo any transformation and can be recovered in a chemically unchanged state.
There are two types of catalysis:-