Question

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

Li2CO3 → LiO + CO2
Li 2 CO 3 → LiO + CO 2

CH4 + O2 → CO2 + 2H2O
CH 4 + O 2 → CO 2 + 2H 2 O

Zn + 2HCl → H2 + ZnCl2
Zn + 2HCl → H 2 + ZnCl 2

CO2 + H2O → CH2OH + O2
CO 2 + H 2 O → CH 2 OH + O 2

Answer 1

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.

Even if the total number of atoms changes, mass may not be conserved in the reaction.
Even if the total number of atoms changes, 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.

Answer 2

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

108 amu
108 amu

215 amu
215 amu

161 amu
161 amu

179 amu

Answer 3

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

Answer 4

The statement that is true regarding a chemical reaction is:

Even if the total number of atoms does not change, mass may not be conserved in the reaction.

Answer 5

To calculate the total mass of the reactants, we need to add up the individual masses of each element present in the reactants.

In FeCl3, we have one Fe atom with a mass of 56 amu and three Cl atoms with a mass of 35 amu each. So, the total mass of FeCl3 is:

56 amu (Fe) + 3 * 35 amu (Cl) = 56 amu + 105 amu = 161 amu

In 3H2O, we have three H atoms with a mass of 1 amu each and two O atoms with a mass of 16 amu each. So, the total mass of 3H2O is:

3 * 1 amu (H) + 2 * 16 amu (O) = 3 amu + 32 amu = 35 amu

Adding the two masses together, we get:

161 amu (FeCl3) + 35 amu (3H2O) = 196 amu

Therefore, the total mass of the reactants is 196 amu.