In which chemical equation is the number of atoms in the reactants the same as the number of atoms in the product?
A. CH4 + O2 → CO2 + 2H2O
B. Li2CO3 → LiO + CO2
C. Zn + 2HCI → H2 + ZnCL2
D. CO2 + H2O → CH2OH + O2
C. Zn + 2HCl → H2 + ZnCl2
Which statement is true regarding a chemical reaction?
A. Even if the total number of atoms changes, mass may not be conserved in the reaction
B. Even if the total number of atoms does not change, mass may not be conserved in the reaction
C. The total number of atoms does not change, so mass is conserved in the reaction
D. The total number of atoms changes, so mass is conserved in the reaction
A. Even if the total number of atoms changes, mass may not be conserved in the reaction
FeCI3 + 3H2O → Fe(OH)3 + 3HCI
Element : Fe, CI, H, O
Mass of an Atom (amu) : 56, 35, 1, 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?
A. 161 amu
B. 108 amu
C. 179 amu
D. 215 amu
To find the total mass of the reactants, we need to calculate the mass of each element in the reactants and then sum them up.
Fe: 1 atom * 56 amu/atom = 56 amu
CI: 3 atoms * 35 amu/atom = 105 amu
H: 6 atoms * 1 amu/atom = 6 amu
O: 3 atoms * 16 amu/atom = 48 amu
Total mass of the reactants = 56 amu + 105 amu + 6 amu + 48 amu = 215 amu
Therefore, the total mass of the reactants is 215 amu.
Answer: D. 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?
A. 38 amu
B. 152 amu
C. 228 amu
D. 76 amu
In a chemical reaction, mass is conserved. Therefore, the total mass of the reactants will be equal to the total mass of the product.
Given that the total mass of the reactants is 76 amu, and the reaction forms a single molecule, the mass of the molecule that is formed will also be 76 amu.
Therefore, the correct answer is:
D. 76 amu
B. Zn + 2HCI → H2 + ZnCL2
C. The total number of atoms does not change, so mass is conserved in the reaction
D. 215 amu
D. 76 amu
are the correct answers
Yes, you are correct. The correct answers are:
B. Zn + 2HCl → H2 + ZnCl2
C. The total number of atoms does not change, so mass is conserved in the reaction
D. 215 amu
D. 76 amu
Thank you for pointing that out.
To determine which chemical equation has the same number of atoms in the reactants as in the products, we need to count the number of atoms on both sides of the equation.
Let's go through each option and count the atoms:
A. CH4 + O2 → CO2 + 2H2O
On the left side, we have 1 carbon atom, 4 hydrogen atoms, and 2 oxygen atoms. On the right side, we have 1 carbon atom, 4 hydrogen atoms, and 2 oxygen atoms. The number of atoms in the reactants is the same as the number of atoms in the products.
B. Li2CO3 → LiO + CO2
On the left side, we have 2 lithium atoms, 1 carbon atom, and 3 oxygen atoms. On the right side, we have 1 lithium atom, 1 oxygen atom, and 2 oxygen atoms. The number of atoms in the reactants is not the same as the number of atoms in the products.
C. Zn + 2HCl → H2 + ZnCl2
On the left side, we have 1 zinc atom and 2 hydrogen atoms. On the right side, we have 1 hydrogen atom, 1 zinc atom, and 2 chlorine atoms. The number of atoms in the reactants is not the same as the number of atoms in the products.
D. CO2 + H2O → CH2OH + O2
On the left side, we have 1 carbon atom and 2 oxygen atoms. On the right side, we have 1 carbon atom, 4 hydrogen atoms, and 1 oxygen atom. The number of atoms in the reactants is not the same as the number of atoms in the products.
Therefore, the only chemical equation in which the number of atoms in the reactants is the same as the number of atoms in the products is:
A. CH4 + O2 → CO2 + 2H2O