A B C these are the answers hopes this help <3
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Answer:</h3>
- They show the elements of make up a compound
- They show the types of atoms that make up a molecule
- They show the number of each type of atom in a molecule
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Explanation:</h3>
To answer this question we need to know what is a compound.
- A compound is a substance that is made by two or more atoms of different elements that are chemically combined.
- A chemical formula of a compound is a formula that shows the elements that make up a compound and also the types of atoms that make up the molecule.
- Additionally, the chemical formula shows the number of each type of atom in a molecule.
- In this case, the chemical formula of a molecule of H₂O shows that it is made up of one hydrogen atom and two oxygen atoms.
Answer : This reaction is an exothermic reaction.
Explanation :
Endothermic reaction : It is defined as the chemical reaction in which the energy is absorbed from the surrounding.
In the endothermic reaction, the energy of reactant are less than the energy of product.
Exothermic reaction : It is defined as the chemical reaction in which the energy is released into the surrounding.
In the exothermic reaction, the energy of reactant are more than the energy of product.
Enthalpy of reaction : It is the difference between the energy of product and the reactant. It is represented as 
.
The balanced chemical reaction will be:
From the reaction we conclude that the heat energy is released during the reaction that means this reaction is an exothermic reaction.
Hence, the reaction is an exothermic reaction.
Answer: m= 3.15x10-3 g NaHCO3
Explanation: To find the mass of NaHCO3 we will use the relationship between moles and molar mass. The molar mass of NaHCO3 is 84 g.
3.75x10-5 moles NaHCO3 x 84 g NaHCO3 / 1 mole NaHCO3
= 3.15x10-3 g NaHCO3
