In which chemical equation is the number of atoms in the reactants the same as the number of atoms in the products?(1 point)
Responses
Zn + 2HCl → H2 + ZnCl2
Zn + 2HCl → H 2 + ZnCl 2
CH4 + O2 → CO2 + 2H2O
CH 4 + O 2 → CO 2 + 2H 2 O
Li2CO3 → LiO + CO2
Li 2 CO 3 → LiO + CO 2
CO2 + H2O → CH2OH + O2
The chemical equation in which the number of atoms in the reactants is the same as the number of atoms in the products is:
CH4 + O2 → CO2 + 2H2O
Which statement is true regarding a chemical reaction?(1 point)
Responses
Even if the total number of atoms does not change, mass may not be conserved in the reaction.
Even if the total number of atoms does not change, mass may not be conserved in the reaction.
The total number of atoms changes, so mass is conserved in the reaction.
The total number of atoms changes, so mass is conserved in the reaction.
The total number of atoms does not change, so mass is conserved in the reaction.
The total number of atoms does not change, so mass is conserved in the reaction.
Even if the total number of atoms changes, mass may not be conserved in the reaction
The statement that is true regarding a chemical reaction is:
The total number of atoms does not change, so mass is conserved in the reaction.
Use the equation and the table to answer the question.
FeCl3 + 3H2O → Fe(OH)3 + 3HCl
Element Mass of an Atom (amu)
Fe 56
Cl 35
H 1
O 16
Iron chloride and water react according to the equation shown. The table shows the atomic masses of the elements involved in the reaction. What is the total mass of the reactants?
(1 point)
Responses
179 amu
179 amu
161 amu
161 amu
108 amu
108 amu
215 amu
To find the total mass of the reactants, we need to calculate the molar mass of each reactant and then multiply that by the stoichiometric coefficient.
FeCl3:
Fe: 1 atom x 56 amu = 56 amu
Cl: 3 atoms x 35 amu = 105 amu
Total mass of FeCl3 = 56 amu + 105 amu = 161 amu
H2O:
H: 6 atoms x 1 amu = 6 amu
O: 3 atoms x 16 amu = 48 amu
Total mass of H2O = 6 amu + 48 amu = 54 amu
Adding the total mass of FeCl3 and H2O:
161 amu + 54 amu = 215 amu
Therefore, the total mass of the reactants is 215 amu.
In a chemical reaction, two molecules with a total mass of 76 amu react to form a single molecule. What is the mass of the molecule that is formed?(1 point)
Responses
228 amu
228 amu
76 amu
76 amu
38 amu
38 amu
152 amu
In a chemical reaction, the total mass of the reactants is always equal to the total mass of the products. Therefore, if two molecules with a total mass of 76 amu react to form a single molecule, the mass of the molecule that is formed must also be 76 amu.
Therefore, the correct answer is:
76 amu
No
It is Zn + 2HCl → H2 + ZnCl2
I apologize for the mistake. Let's calculate the mass of the molecule that is formed.
Zn: 1 atom x atomic mass of Zn (65 amu) = 65 amu
HCl: 2 atoms of H x atomic mass of H (1 amu) + 1 atom of Cl x atomic mass of Cl (35 amu) = 2 amu + 35 amu = 37 amu
H2: 2 atoms x atomic mass of H (1 amu) = 2 amu
ZnCl2: 1 atom of Zn x atomic mass of Zn (65 amu) + 2 atoms of Cl x atomic mass of Cl (35 amu) = 65 amu + 2 x 35 amu = 65 amu + 70 amu = 135 amu
Adding the masses:
65 amu + 2 x 37 amu = 65 amu + 74 amu = 139 amu
Therefore, the mass of the molecule formed in the reaction is 139 amu.
This is my answer to the FIRST question. I have not looked mat the ,later ones.
No
It is Zn + 2HCl → H2 + ZnCl2