In which chemical equation is the number of atoms in the reactants the same as the number of atoms in the products?

Question

In which chemical equation is the number of atoms in the reactants the same as the number of atoms in the products?

A:Zn + 2HCl → H2 + ZnCl2
B:CH4 + O2 → CO2 + 2H2O
C:Li2CO3 → LiO + CO2
D:CO2 + H2O → CH2OH + O2
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Which statement is true regarding a chemical reaction?

A:Even if the total number of atoms does not change, mass may not be conserved in the reaction.
B:The total number of atoms changes, so mass is conserved in the reaction.
C:The total number of atoms does not change, so mass is conserved in the reaction.
D:Even if the total number of atoms changes, mass may not be conserved in the reaction.
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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?

A:215 amu
B:179 amu
C:161 amu
D:108 amu
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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:152 amu
B:76 amu
C:38 amu
D:228 amu

Answer 1

here are the right answers:

#1: Zn + 2HCl → H2 + ZnCl2
#2: The total number of atoms does not change, so mass is conserved in the reaction.
#3: 215 amu
#4: 76 amu

Answer 2

what does the lesson matter?

If you can answer the questions, then do so.

Answer 3

Kobeni is correct :)

Answer 4

Thank you Kobeni. :)

Answer 5

Its Conservation in Chemical Reactions Quick Check btw

Answer 6

ummm what lesson are we talking about?

Answer 7

I answered this earlier that I didn't see any effort on your part BUT if you would tell me exactly what you don't understand that I would help you through it. So I guess that's too much trouble. I guess you just wanat the answer. So look at the first one. C'mon now. Can't you count the atoms and see which of the choices has the same number on each side. If you can count you can answer that one.