In the reaction $2{\text{H}}_2\text{O}2\backslash text\{H\}\_2\backslash text\{O\}$​ ​​​​​​​​​​​​​​​​​→ $2{\text{H}}_2+{\text{O}}_{2}2\backslash text\{H\}\_2+\backslash text\{O\}\_2$​​​​​​​​​​​​​​​, how many hydrogen (H) atoms are there in 2 molecules of ${\text{H}}_2\text{O}\backslash text\{H\}\_2\backslash text\{O\}$​​​​​​​​​​​​​​​?

Which of the following is correct for the word equation: Magnesium + Oxygen → Magnesium oxide?

Which of the following is a synthesis reaction?

In the equation $\text{Fe}\backslash text\{Fe\}$​​​​​​​​​​ + ${\text{O}}_2\backslash text\{O\}\_2$​​​​​​​​​​ → ${\text{Fe}}_2{\text{O}}_3\backslash text\{Fe\}\_2\backslash text\{O\}\_3$​​​​​​​​​​, what is the coefficient of Fe?

The reaction $\text{Zn + HCl}\backslash text\{Z\}\backslash text\{n\; +\; HCl\}$ → ${\text{ZnCl}}_2+{\text{H}}_2\backslash text\{ZnCl\}\_2+\backslash text\{H\}\_2$​​​​ is balanced by which set of coefficients?

Balance the equation: $\text{C}+{\text{O}}_2\backslash text\{C\}+\backslash text\{O\}\_2$​​​​ → ${\text{CO}}_2\backslash text\{CO\}\_2$​​​​​.​ What is the coefficient of O₂?

Which of these equations is balanced?

Balance the equation: $\text{Al}+{\text{O}}_2\backslash text\{Al\}+\backslash text\{O\}\_2$​ ​​​​→ ​${\text{Al}}_2{\text{O}}_3\backslash text\{Al\}\_2\backslash text\{O\}\_3$​​​​. What are the correct coefficients?

Which of the following is correctly balanced?

Balance the equation: $\text{Fe}+{\text{Cl}}_2\backslash text\{Fe\}+\backslash text\{Cl\}\_2$​​​​​ → ${\text{FeCl}}_3\backslash text\{FeCl\}\_3$​​​​​.​ What are the coefficients?

Balance the equation: $\text{Na}+{\text{H}}_2\text{O}\backslash text\{Na\}+\backslash text\{H\}\_2\backslash text\{O\}$​​​​​ → $\text{NaOH}+{\text{H}}_2\backslash text\{NaOH\}+\backslash text\{H\}\_2$​​​​.​ What are the coefficients?

Balance the equation: $\text{K}+{\text{Br}}_2\backslash text\{K\}+\backslash text\{Br\}\_2$​​​​​ → $\text{KBr}\backslash text\{KBr\}$​​​​.​ What are the coefficients?

Balance the equation: $\text{Al}+\text{HCl}\backslash text\{Al\}+\backslash text\{HCl\}$​​​​​ → ${\text{AlCl}}_3+{\text{H}}_2\backslash text\{AlCl\}\_3+\backslash text\{H\}\_2$​​​​.​ What are the coefficients?

Balance the equation: $\text{Na}+{\text{Cl}}_2\backslash text\{Na\}+\backslash text\{Cl\}\_2$​​​​​ → $\text{NaCl}\backslash text\{NaCl\}$​​​​. What are the coefficients?

Balance the equation: ${\text{H}}_2+{\text{F}}_2\backslash text\{H\}\_2+\backslash text\{F\}\_2$​​​​​ → $\text{HF}\backslash text\{HF\}$​​​​.​ What are the coefficients?

Balance the equation: $\text{P}+{\text{O}}_2\backslash text\{P\}+\backslash text\{O\}\_2$​​​​​ → ${\text{P}}_2{\text{O}}_5\backslash text\{P\}\_2\backslash text\{O\}\_5$​​​​.​​ What are the coefficients?

Which of the following is balanced?

Balance the equation: ${\text{C}}_3{\text{H}}_8+{\text{O}}_2\backslash text\{C\}\_3\backslash text\{H\}\_8+\backslash text\{O\}\_2$​​​​​​ → ${\text{CO}}_2+{\text{H}}_2\text{O}\backslash text\{CO\}\_2+\backslash text\{H\}\_2\backslash text\{O\}$​​​​​.​​ What are the coefficients?

Balance the equation: $\text{Ca}+{\text{N}}_2\backslash text\{Ca\}+\backslash text\{N\}\_2$​​​​​ → ${\text{Ca}}_3{\text{N}}_2\backslash text\{Ca\}\_3\backslash text\{N\}\_2$​​​​.​ What are the coefficients?

Balance the equation: $\text{KCl}{\text{O}}_3\backslash text\{KCl\}\backslash text\{O\}\_3$​​​​ → $\text{KCl}+{\text{O}}_2\backslash text\{KCl\}+\backslash text\{O\}\_2$​​​.​ What are the coefficients?

Balance the equation: $\text{Fe}+\text{S}\backslash text\{F\}\backslash text\{e\}+\backslash text\{S\}$​​​​​ → $\text{FeS}\backslash text\{FeS\}$​​​​.​ What are the coefficients?

Balance the equation: ${\text{H}}_2+{\text{I}}_2\backslash text\{H\}\_2+\backslash text\{I\}\_2$​​​​ → $\text{HI}\backslash text\{HI\}$​​​.​ What are the coefficients?

Balance the combustion of methane: ${\text{CH}}_4+{\text{O}}_2\backslash text\{CH\}\_4+\backslash text\{O\}\_2$​​​​ → ${\text{CO}}_2+{\text{H}}_2\text{O}\backslash text\{CO\}\_2+\backslash text\{H\}\_2\backslash text\{O\}$​​​.​​ What are the coefficients?

Balance the equation: Na₂O → Na + O₂. What are the coefficients?

Balance the equation: H₂ + Br₂ → HBr. What are the coefficients?