Question
8 chem questions :) 10 pts right first answer :]?
Question 1 (Multiple Choice Worth 2 points)
Which of the following compounds will produce H2O as one of the products when it decomposes?
Cu(OH) 2
Hg(ClO3)2
MgCO3
CaO
Question 2 (Multiple Choice Worth 2 points)
Which of the following is a product formed when SO2 and H2O react together?
SO3
H2SO3
H2O
HSO2
Question 3 (Multiple Choice Worth 2 points)
Which of the following is a product formed when CaCO3 decomposes?
Ca2
O2
CO2
CaO2
Question 4 (Multiple Choice Worth 2 points)
Which of the following combinations of reactants will result in a synthesis reaction?
Cl2 + HBr
Ca + H2O
MgO + H2O
C2H2 + O2
Question 5 (Multiple Choice Worth 2 points)
Which of the following is a synthesis reaction?
C2H4 + 3 O2 2 CO2 + 2 H2O
2HBr H2 + Br2
CO2 + H2O H2CO3
F2 + 2 HCl Cl2 + 2 HF
Question 6 (Essay Worth 4 points)
Give the complete balanced equation for the reaction that occurs when lithium carbonate (Li2CO3) is heated. You do not need to make the subscripts smaller in your answer, just write them out as regular numbers. For example: Li2CO3.
Question 7 (Multiple Choice Worth 2 points)
Which statement below is not true of decomposition reactions?
They usually require the addition of energy for the reaction to occur.
They produce more than one product at the end of the reaction.
They begin with more active reactants and end with less active products.
They have one compound as the reactant at the beginning of the reaction.
Question 8 (Essay Worth 4 points)
Write the complete balanced equation for the reaction between lead (IV) oxide (PbO2) and water (H2O). You do not need to make the subscripts smaller; just write them out as regular numbers. For example: PbO2.
Answers
THE ABOVE ANSWER IS WRONG- CHECK YOUR REFERENCE TABLE FOR SOLUBILITY: LEAD (IV) OXIDE IS INSOLUBLE IN WATER. ETC ETC> lol
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1) Cu(OH)2
2)H2SO3 [sulfurous acid- not sulfuric which would be H2SO4]
3)CO2 [decomposition of metal carbonates always = metal oxides and CO2]
4)MgO + H20 = Mg(OH)2 [answers 1 and 2 are single replacement reactions and 4 is combustion]
5)CO2 + H20 H2CO3 [Carbonated Water!]
6) Li2CO3 --> Li2O + CO2 [the equation is already balanced- take stock: 4 Li, 2 C, 6 O]
7) 3 is false
8) I spent a long time trying to figure this out. Then I realized that Lead(IV) Oxide- Which is Lead Dioxide is virtually insoluble in water. Go figure. Your teacher is trying to trick you.
Cu(OH) 2 only one having both O and H
H2SO3
CO2
MgO + H2O
CO2 + H2O H2CO3
2Li2CO3 + heat --> 4Li + 2CO2 +O2
They usually require the addition of energy for the reaction to occur
2PbO2 + 2H2O --> 2Pb(OH)2 + O2