Answer:
a. Heat is often absorbed during reactions.
c. Heat is often released during chemical reactions.
Explanation:
Thermochemistry -
The study of thermochemistry involve the change in the amount of heat , during any physical or chemical process , is referred to as thermodynamics .
The focus of thermochemistry is on the changing amount of energy in the form of heat , on the system with respect to the surroundings .
The process like boiling , melting , sublimation , may require energy or releases energy , and hence are studied under thermochemistry .
Hence , from the given question ,
The correct options are - a , c.
<span>6s²4f¹⁴5d¹⁰6p²
6 shows that the element is in the 6 period,
6p² shows that the element is in the 14th group. (1 and 2 groups have s -electrons as last ones, 13 group has s²p¹, and 14 group has s²p²)
The element is Pb.
</span>
Answer: 2.62 x 10^22 atoms
Explanation:Please see attachment for explanation
Less stable should be the answer.as I think
I hope this helps you
Answer is: this is synthesis reaction.<span>
</span>Chemical reaction: Ba + F₂ → BaF₂.
Synthesis reaction<span> is a type of reaction in which multiple reactants combine to form a single product.
</span>In barium fluoride, barium has oxidation number +2 and fluorine has oxidation number -1, so compound has neutral charge.