Answer: The correct option is A.
Explanation: In a chemical reaction, reactants react to form a number of products.
For the formation of products, the bonds of the individual reactants must be broken and the bonds of the products must be formed.
For example: Formation of water from hydrogen gas and oxygen gas. Reaction follows:

The Bonds of hydrogen and oxygen molecule are broken and new bonds between hydrogen and oxygen atoms are formed to give water molecule.
Answer:

Explanation:
Hello!
In this case for the solution you are given, we first use the mass to compute the moles of CuNO3:

Next, knowing that the molarity has units of moles over liters, we can solve for volume as follows:

By plugging in the moles and molarity, we obtain:

Which in mL is:

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Answer:</h2>
The magnesium ribbon, <u>D. It forms a material to cast the tool mark</u>.
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Explanation:</h2>
When a magnesium ribbon is burnt in the presence of oxygen it gives out strong light and heat is produced. Apart from it, it leads to the production of substance called as magnesium oxide which is formed as the product due to the reaction of magnesium with the oxygen present in the air.
Tool marks are the mark which is created by tools while using them. In order to identify or locate them castes made up of magnesium oxide is utilized. When this is pasted on the suspected area, the tool mark of the suspected tool gets pasted on it.
John Dalton made some hypothesis about the structure of atom. He proposed that matter is composed of great number of indivisible particles called atoms they can neither be destroyed nor be created.
<h3>What is atomic theory?</h3>
There are different theories regarding the structure and electronic properties of an atom. Many scientists contributed to the modern theory of atomic structure in which John Dalton was first to mention the word atom.
According to Dalton' theory, matter is composed of indivisible particles called atoms. Atoms can neither be created nor be destroyed. All the atoms of the same element are identical in all aspects.
Atoms of different elements are different and the compounds are formed by the combination of atoms. Dalton's theory provided a sound basis for the laws of chemical combination and also several properties of gases and liquids known at that time.
However, he could not explain the reason for chemical combination of atoms and did not give any idea about the existence of isotopes and isobars.
Hence, the main aspects of Dalton's theory was the indivisibility of atoms and the chances of chemical combination.
To learn more about Dalton's theory, find the link below:
brainly.com/question/11855975
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