Answer:
19. 1, 2, 3, 4, 5, 6, 7, 8
20. Li=1+, Be=2+, B=3+, C=4+
21. N=3-, O=2-, F=1-
Explanation:
Key feature of a Bronsted Lowry base : The notable feature of all bronsted lowry bases is that they contain atleast one electron lone pair, which is available for interaction with a proton, and allows the base to act as a proton acceptor.
<h3>What do we know about Bronsted Lowry Base?</h3>
Any species that can receive a proton and needs one pair of electrons to attach to the H+ is referred to as a Bronsted-Lowry base. Since water is amphoteric, it may function as both a Brnsted-Lowry acid and a base.
The Brønsted–Lowry theory is an acid–base reaction theory which was proposed independently by Johannes Nicolaus Brønsted and Thomas Martin Lowry in 1923.
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Answer:
B. Mechanical waves must travel through a medium, but electromagnetic waves do not require a medium.
Explanation:
A wave is defined as any disturbance that transmits energy from one point to another.
Waves can be typically classified as either mechanical or electromagnetic waves.
Mechanical waves are waves that requires a medium for their propagation. In a vacuum, they cannot be propagated and would not cause any disturbance. An example is sound waves.
Electromagnetic waves do not require a medium to be propagated. They can pass through any substance in nature. Electromagnetic radiations belongs to this class.
<u>Answer:</u> The indicators written will identify a new substance is formed in a chemical equation.
<u>Explanation:</u>
A chemical equation is defined as the equation in which reactants and products are present and are separated by a right arrow.
Indicators of a chemical reaction are:
- Formation of a precipitate
- Evolution of gas
- Formation of bubbles
- Color change
- Specific odor
- Change in temperature
Hence, the indicators written will identify a new substance is formed in a chemical equation.
