Answer:
For the first reaction the reagents are: MgCl2 and Na2CO3
For the second reaction the reagents are: Na2HPO4 and CaCl2
Explanation:
Precipitation reactions lie in the production of a compound that is not soluble, which is called a precipitate, this precipitate is produced when two different solutions are combined, each of which will contribute an ion for the formation of the precipitate. In the first reaction you have:
MgCl2 + Na2CO3 = MgCO3 + 2 NaCl
Type of reaction: double displacement
The second reaction is as follows:
4Na2HPO4 + 3CaCl2 → Ca3 (PO4) 2 + 2NaH2PO4 + 6NaCl
It is the reaction of sodium hydrochlorophosphate and calcium chloride
Answer:
No
Explanation:
In the left side of the reaction, there are 6O and 3C but on the right side, there are only 1C and 2O
<u>Solution</u> : Emperical Formula = 
Emperical Formula - A formula that gives the simplest whole number ratio of atom in a compound.
In the question percentages are given then assume that the total mass is 100grams so that the mass of each element is equal to the percentage given.
Given : 80.0g Carbon
20.0g Hydrogen
First convert the given masses into moles.


Value of each mole divided by the smallest number of moles and then round off.
Moles ratio of the element are


This is the mole ratio of the elements and is repersented by the subscript in the emperical formula.
Emperical Formula = 
Answer:
Reactants have more energy than products
Explanation:
Generally, in an exothermic reaction heat is released. In other words, energy is released. So you start with reactants which have a set amount of stored chemical energy, and you lose some in the reaction. Since energy is 'leaving', the stored chemical energy in the products is less than what we started with in the reactants. When given a graph, you can tell this is true because going from left to right, the line representing the stored chemical energy will start at a higher level than where it ends.