Identify the following as combination, decomposition, replacement, or ion exchange reactions: znco3(s) → zno(s) + co2 ↑ 2 nabr(aq) + cl2(g) → 2 nacl(aq) + br2(g) 2 al(s) + 3 cl2(g) → 2 alcl3(s) ca(oh)2(aq) + h2so4(aq) → caso4(aq) + 2 h2o(l) pb(no3)2(aq) + h2s(g) → 2 hno3(aq) + pbs↓ c(s) + zno(s) → zn(s) + co↑

Explanation:

ZnCO₃(s) → ZnO(s) + CO₂ ↑

      Decomposition reaction:

This involves the breakdown of a compound into its component individual elements or other compounds.

2NaBr(aq) + Cl₂(g) → 2NaCl(aq) + Br₂(g)

        Replacement reaction

This is a single replacement reaction in which one substance replaces the other.

2Al(s) + 3Cl₂(g) → 2AlCl₃(s)

  Combination reaction:

Here, a single compound forms from two or more reacting species.

Ca(OH)₂(aq) + H₂SO₄(aq) → CaSO₄(aq) + 2H₂O(l)

Replacement reaction:

This is a double replacement reaction in which ions are exchanged to form new compounds.

Pb(NO₃)₂(aq) + H₂S(g) → 2HNO₃(aq) + PbS↓

Replacement reaction:

This is a double replacement reaction in which ions are exchanged to form new compounds.

C(s) + ZnO(s) → Zn(s) + CO↑

Replacement reaction

This is a single replacement reaction in which one substance replaces the other.

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer