Answer : Chemicals A and B form an endothermic reaction, and chemicals C and D form an exothermic reaction.
Explanation :
Endothermic reaction : When the system absorb heat from the surrounding then the surrounding become cool.
Exothermic reaction : when the system releases heat into the surrounding then the surrounding become hot.
According to the question,
when we mixed chemical A and chemical B together in a test tube to form chemical C, the mixture become cool. This means that the system is absorbing heat from the surrounding and thus the reaction is called a endothermic reaction.
And when we added chemical D in chemical C, the new mixture becomes hot and explodes. This means that the system is releasing heat into the surrounding and thus the reaction is called as exothermic reaction.
Answer:
between the 2 and the 3 shell
Explanation:
when a gain of energy is the displacement of the electrons in a layer of low-energy shell high-energy, and here we have the 2nd shell is the shell of low energy, and 3 shell the shell is high-energy.
The valence electrons are shared between the atoms
Answer:
to validate the law of conservation of mass as total no. of reactants must be equal to the total no. of products
Answer: A comprehensive legal term for uniform standards ascribed to the quantity, capacity, volume, or dimensions of anything. Legislation that adopts and mandates the use of a uniform system of weights and measures is a valid exercise of Police Power, and such laws are constitutional.
Explanation:
