Answer:
1. CaCO3 + 2HCl —> CaCl2 + H2O + CO2
2. Mg(OH)2 + 2HCl —> MgCl2 + 2H2O
3. Na2CO3 + 2HCl —> 2NaCl + H2O + CO2
It will have an overall positive charge.
Answer: The coefficient in front of AgCl when the equation is properly balanced is 2.
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
Decomposition is a type of chemical reaction in which one reactant gives two or more than two products.
Decomposition of silver chloride is represented as:

Thus the coefficient in front of AgCl when the equation is properly balanced is 2.
Answer:
This would support Dalton's postulates that proposed the atoms are indivisible because no small particles are involved.
Explanation:
Experiment using the gas discharge tube by J.J Thomson led to the discovery of cathode rays which are now known as electrons.
Primarily, Thomson's experiment led to the discovery of cathode rays, electrons, as subatomic particles.
If the size of the atoms observed at the cathode is the same as that of the rays,we can conclude that the particles of the rays are the simplest form of matter we can have. This would suggest that the atom is indeed the smallest indivisible particle of a matter according to Dalton.
Nucleic acids are hydrocarbons that also contain nitrogen, phosphorus and oxygen elements.
Hydrocarbons are long chains of carbon that have additional bonds exclusively with hydrogen atoms. They are hydrophobic, or not soluble in water. Nucleic acids are macromolecules that are made of units called nucleotides, they are mainly in two forms; the RNA and and the DNA. Both the RNA and DNA have a pentose sugar, a phosphate, and a nitrogen containing base.