Answer:
1. Lanthanum-139 atom is the stable isotope of lanthanum with relative atomic mass 138.906348, 99.9 atom percent natural abundance and nuclear spin 7/2.
2. In fact, over 80% of electric cars sold globally utilized permanent magnet-based motors in 2019. These magnets are typically made with rare-earth materials such as neodymium and dysprosium, which have a very geographically constrained supply chain.
3. It is the second most reactive of the rare-earth metals after europium. Lanthanum oxidizes in air at room temperature to form La2O3. It slowly reacts with water and quickly dissolves in diluted acids, except hydrofluoric acid (HF) because of formation of a protective fluoride (LaF3) layer on the surface of the metal.
Explanation:
<h3><u>Answer;</u></h3>
Cannon-Bard theory
<h3><u>Explanation</u>;</h3>
- <em><u>The idea that an emotion-arousing stimulus is simultaneously routed to the cortex and to the sympathetic nervous system is central to the Cannon-Band theory.</u></em>
- Cannon-Bard theory states that we feel emotions and experience physiological reactions such as sweating, trembling, and muscle tension simultaneously.
- The theory argues that we experience physiological arousal and emotion at the same time. The theory gives more attention to the role of thought or outward behavior as compared to James-Lange.
