#42 the equation for the formation of water from its elements, h 2 (g) + o 2(g) h 2 o (l) can be...
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#42 The equation for the formation of water from its elements, H2 (g) + O2(g) H2O(l) can be “balanced”by changing the formula of the product toH2O2. Explain why this is incorrect.
To change the subscripts like thatactually changes the product to a totally different one. You cannot touch the subscripts to “balance” theequation, only add coefficients.
#43. Balance the following equations:
a. PbO2 PbO + O22 2
b. Fe(OH)3 Fe2O3 + H2O2 3
c. (NH4)2CO3 NH3 + H2O + CO2
d. NaCl + H2SO4 Na2SO4 + HCl2
2
2
#44 What is a characteristic of every combination reaction?
Every combination reaction has a single product. example:
2H2 + O2 2H2O
single product
#45 Write balanced chemical equationsfor the following combination reactions.
b. P + O2 diphosphorous pentoxide
4P + 5O2 2P2O5
c. Ca + S CaS
a. Mg + O2 2MgO2
#46 What is a distinguishing feature of every decomposition reaction?
a decomposition always has a singlereactant. example:
2H2O 2H2 + O2
#47 Write a balanced chemicalequation for each decompositionreaction:
a. Ag2O(s) Ag + O22
b. ammonium nitrate dinitrogen monoxide
+ water NH4NO3 N2O + 2H2O
4
#48 Use the activity series of metalsto write a balanced equation for eachsingle-replacement reaction.
a. Au(s) + KNO3NO reaction. K ishigher on the chartthan Au
b. Zn(s) + AgNO3
c. Al(s) + H2SO4
Zn(NO3)2(s) + Ag22
Al2(SO4)3 + H22 3 3
#49 write a balanced equationfor each of the following double-replacement reactions.
a. H2C2O4(aq) + 2KOH(aq)
2H2O + K2C2O4
b. CdBr2(aq) + Na2S(aq)
CdS + 2NaBr
#50 What is common to all combustionreactions?
oxygen on the left side
example:
C4H8 + 6O2 4CO2 + 4H2O
#51 Write a balanced equation forthe complete combustion of eachcompound.a. Butene (C4H8)
C4H8 + 6O2 4CO2 + 4H2O
b. acetone (C3H6O)
C3H6O + 4O2 3CO2 + 3H2O
#52 Balance each equation and identifyits type.
a. Hf + N2 Hf3N43 2a combination reaction
b. Mg + H2SO4 MgSO4 + H2
a single-replacement reaction
c. C2H6 + O2 CO2 + H2O642 7
a combustion
#52 Balance each equation and identifyits type.continued….
d. Pb(NO3)2 + NaI PbI2 + NaNO32 2
e. Fe + O2 Fe2O334 2
a double-replacement reaction
a combination reaction