Answer:
The attractive forces must be overcome are :
Explanation:
For the compound to dissolve the attractive forces existing between atoms of the compound must be reduced
<u>CsI is ionic compound </u><em>and its molecules are held together by ionic(electrostatic) force . These force must be weakened for its dissolution</em>
Forces in HF <em>:</em>
<em>1 .Hydrogen Bonding : In HF strong intermolecular Hydrogen Bonding exist between the electronegative F and Hydrogen</em>
2. Dipole - dipole : <em>HF is polar . So it is a permanent dipole and has dipole diople interaction</em>
Answer:
Thermal energy (also called heat energy) is produced when a rise in temperature causes atoms and molecules to move faster and collide with each other. The energy that comes from the temperature of the heated substance is called thermal energy.
Credit:
https://www.solarschools.net/knowledge-bank/energy/types/thermal
Because each element has an exactly defined line emission spectrum, scientists are able to identify them by the color of flame they produce.
Answer:
Option C = same period.
Explanation:
All these elements belongs to second period of periodic table. This period consist of eight elements lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine and neon.
Electronic configuration of lithium:
Li₃ = [He] 2s¹
Electronic configuration of beryllium:
Be₄ = [He] 2s²
Electronic configuration of boron:
B₅ = [He] 2s² 2p¹
Electronic configuration of carbon:
C₆ = [He] 2s² 2p²
Electronic configuration of nitrogen:
N₇ = [He] 2s² 2p³
Electronic configuration of oxygen:
O₈ = [He] 2s² 2p⁴
Electronic configuration of fluorine:
F₉ = [He] 2s² 2p⁵
Electronic configuration of neon:
Ne₁₀ = [He] 2s² 2p⁶
All these elements present in same period having same electronic shell.
However their families, valance electrons and group are different. Boron have three valance electrons and belongs to group 3A. Carbon belongs to group 4A and have 4 valance electrons. Nitrogen belongs to group 5A and have five valance electrons. Oxygen belongs to group 6A and have six valance electrons. Fluorine belongs to group 7A and have seven valance electrons.
Mixture is composed of molecules of different types. A compound can only be separated through chemical means. While a compound is a pure substance that contains 2 or more elements chemically combined together while a mixture are formed when two substances are added together without chemical bonds being formed.